The Books


THE CHARACTERS

Elena Gilbert 

Elena is described as having eyes the color of lapis lazuli (a deep, dark blue) with gold flecks in them; this is meant to be a parallel to the lapis lazuli rings that vampires must wear to stay alive in the sunlight. In some scenes, her eyes are mentioned as having some violet in them as well, as when she wears her violet-colored homecoming dress which then "brings out the violet in her eyes."
Elena's hair is long and straight, and a soft gold, described as being a few shades lighter than Katherine's, while her eyebrows and lashes are a darker blonde. Her skin is very fair and almost translucent, sometimes described as being like a magnolia flower, or like porcelain, and doesn't tan easily. She's fairly slim, about average for a teenage girl, and very pretty. Elena is taller than Katherine by "a good handspan.
Although everyone seems to be convinced of Elena's intelligence, her academic performance actually seems somewhat uneven. Mr. Tanner says that Elena is failing history, and no one corrects him. Elena says she doesn't care if she fails trigonometry. She is enrolled in a General Business class even though she is a senior.
After Elena is dead (following Katherine's death), Bonnie describes her: She wasn't a saint. She wasn't always sweet and good and honest and agreeable. But she was strong and loving and loyal to her friends, and in the end she did the most unselfish thing anybody could do.
Elena lives with her aunt, Judith Gilbert, and her little four-year-old sister, Margaret Gilbert. Her parents died in a car crash quite some time prior to the events of the books, not long after Margaret was born, so sometime around 1987-1988.
Judith's fiancée Robert also plays a role in the family dynamic, but is a hesitant, hands-off father figure and more present as an influence on Margaret than Elena.
Elena is dating Matt Honeycutt at the beginning of the series, but breaks up with him to pursue Stefan Salvatore. Elena and Matt remain friends.
Stefan and Elena become a couple after the Homecoming Dance (original series). However, in 'The Return' series, she realizes that she also has feelings for Damon.
Elena's closest friends are Meredith Sulez and Bonnie McCullough. She was also friends with Caroline Forbes until the beginning of the series.

Stefan Salvatore
"From where she stood, Elena could see he had a lean, flat-muscled body. Faded jeans he probably had to peel off at night, tight T-shirt, and a leather jacket of unusual cut. His hair was wavy—and dark."
[...]
"The dark curly hair framed features so fine that they might have been taken from an old Roman coin or medallion. High cheekbones, classical straight nose... and a mouth to keep you awake at night, Elena thought. The upper lip was beautifully sculpted, a little sensitive, a whole lot sensual."

– The Awakening

Stefan is average male height, slightly taller than his brother Damon. He is described as being gorgeous, with forest green eyes, curly or wavy jet black hair, and strong, sculptural features. Stefan and Damon look very similar.
Stefan tends to wear expensive clothing, usually in black. Part of this is because he was once a member of the Italian nobility, and his tutor taught him to dress as befitted his position. However, he has been spotted on several occasions in T-shirts and jeans, and he shows an odd penchant for sweaters.
Much of Stefan's personality is influenced by the guilt and self-hatred he feels over his vampiric nature and the circumstances surrounding his "death." Readers have often called him mopey, moody, angsty, and broody. However, while Stefan does have a tendency to blame himself for things, which leads to periods of intense depression, he is also very kind, compassionate, responsible, chivalrous, and brave. He has strong morals and a strict code of ethics, probably influenced by his tutor and Catholic upbringing.
Growing up in Florence, Stefan comes across as reclusive, though his brother does admit he has friends. According to Damon, Stefan spends his time "among books and paintings," and has never had to face reality because of his sheltered life. He seems quite naive, and a bit of a romantic where Katherine (and later Elena) are concerned.
Following Katherine's "suicide" and his transformation into a vampire, Stefan spends the next 500 years consumed with guilt. He refuses to drink human blood, and chooses to live in the shadows. Upon his arrival to Fell's Church, he attempts to blend in with the other students at Robert E. Lee High School. Yet, his reserved nature keeps him from making friends until Matt Honeycutt - the school quarterback - comes along. Matt can sense Stefan is incredibly lonely.
Though Stefan is usually very gentle, he has a bit of a temper (especially whenever his brother Damon is involved). When he gets angry he shows violent tendencies, and can lose control. Damon describes him as selfish, and at times he does seem self-absorbed in his own problems. However, whenever the town or his friends are in danger, Stefan will rush over to try to help. He has a strong sense of duty and loyalty. He has also been shown to be willing to sacrifice himself in order to save the people he cares about.
Finally, Stefan's personality is not all doom and gloom. He displays a wicked sense of humor on several occasions, and when he's around his friends, he relaxes and lets his guard down. Sometimes he even smiles.
Stefan's code of ethics forbid him from drinking human blood. He also believes it wrong to use his powers against those who are weaker than him, and he does so only sparingly (though he seems to have no problem with getting Damon to use his powers on others). His decision to live off the blood of animals makes his Power weaker than other vampires. Yet, he does have superhuman strength and agility, and he can influence people's minds.
In The Struggle, Stefan breaks his promise to himself and drinks human blood. This gives him the power to change into an animal form, and he transforms into a hawk.

Damon Salvatore
"He was remarkably good-looking. His face was pale in the artificial twilight, but she could see that his features were cleanly defined and nearly perfect under a shock of dark hair. Those cheekbones were a sculptor's dream."
[...]
"God, he was beautiful. Handsome was too weak and colorless a word."
[...]
"He had taken a step closer, and she could see that those eyes were unusual, almost black, but with odd lights in them. As if you could look deeper and deeper until you fell into them, and went on falling forever." - The Awakening, ch.10

Damon is described as being gorgeous, with straight black hair and black eyes with "odd lights in them." He is slightly shorter than his brother Stefan, and resembles him greatly. Stefan, also in The Awakening, remembers a human Damon with a magnetism that drew women to him "like moths to a flame," so his charisma is not entirely due to his vampire nature.
Damon most often wears black. He seems to favor black leather riding boots as footwear, black jeans, a black belt, black sweater and a black leather jacket.
Hair black with rainbow lights in it, like a crow's feathers, or 'like liquid, too soft and fine for human hair.' Eyes that are black, 'fathomless and full of strange lights' and which have a tendency to 'fill the universe.' He's middling-verging-on-short, and has 'dark beauty and grace and the sensuality that drew women to him like moths to a flame.' He tends to lounge in a way that should get him done for harassment but can take 'lithe stalking steps.' He usually wears all black, mirrored sunglasses and drives a black Ferrari with 'illegally tinted' windows. He has a 'very engaging' laugh and a 'charming' smile.

'God, he was beautiful. Handsome was too weak and colorless a word.'

Damon is self-contained and reserved on the surface most of the time, only letting his emotions through when he's angry - usually at Stefan. He generally acts flippant and arrogant, and constantly plays word games, especially when it comes to dancing around an issue, and even more especially when that issue involves his true feelings on a serious subject.
Damon has an aristocratic, elegant demeanor, and a very pragmatic outlook on life. He believes that the vampire nature is inherently dark, and that Stefan's attempts to not feed on humans are therefore unnatural. He has no problem with killing humans, although he generally won't go out of his way to do so. He kills Mr. Tanner, but claims he did so only because Tanner pulled a knife on him and that it was thus self-defense. He has no problem threatening children, though - since Elena gives in to his blackmail - it'll never be known whether he really would've gone through with his threats to hurt Margaret.
He has a significantly violent history due to his early vampire life, when he started his own mercenary company. Although we are given no glimpses into this mercenary life, it is strongly implied that he did immoral things with no regrets, and would have little to no problem doing them again.
During the course of the original four books, it is implied that Damon may have a renewed respect for human beings as something other than food. As he spends more time around the human characters, he seems to warm up to them a bit more and treat them less like potential meals and more like acquaintances, almost even friends. He sometimes even seems frustrated by his own unwillingness to be straight with them, as exemplified by his inability to rescue Vickie in book 4; Stefan reams him out for several paragraphs before Damon finally explains the real reason he couldn't help her.
Damon was born in the 15th century in Florence, Italy. It is assumed that he is the oldest son of Giuseppe di Salvatore, a Conte (count). Some years later (an exact number isn't provided), his brother Stefan was born. Damon and Stefan's mother fell ill and died a few years after that. Allegedly, he blames his little brother for her death and has never forgiven him (it seems likely, but the reader has only Stefan's suspicion that this is so, as Damon himself never suggests anything of the sort).
Damon was sent to a university as an adult but wasted all of his time there gambling, hawking, and womanizing, while sending his tutors to do his work for him instead. He ignored his father's demands that he straighten up, and the animosity between him and Giuseppe grew. Damon began to resent his father, feeling that Giuseppe let his friends mooch off and make a laughingstock out of him.
On one of his returns from university, Damon met Katherine, the daughter of Baron von Schwartzschild, who was staying with the di Salvatore family for her health while her father traveled on business. Although Stefan was already romancing her, at some point while he wasn't looking, Damon also befriended and seduced Katherine. It is unclear how far the seduction went physically, or how much investment Damon had in it emotionally. Damon and Stefan both found out about Katherine's vampire nature, and Katherine came to both brothers separately in the night and shared blood with them, each not knowing that the other was getting the same treatment.
After the two brothers demanded that Katherine choose one of them for her husband, or neither, Katherine chose both of them and provided each of them with a lapis lazuli ring. Damon and Stefan, infuriated, almost fought one another on the spot, but Katherine ran away crying when they wouldn't stop fighting, even for her sake. The next day, Damon and Stefan found Katherine's new white dress smoldering with ashes and remains of burning flesh, and a suicide letter telling them that she wants her death to bring them together.
Enraged, Stefan and Damon grabbed their swords and began dueling. Damon pierced Stefan's heart, possibly by accident, because he then leaned down to check on Stefan. As he did so, Stefan's last dying act was to stab Damon through the heart as well. Damon later woke up, just like Stefan, in their family crypt, now a vampire. A few days later, Damon chased Stefan out of Florence altogether and warned him never to return.
The only things known about Damon during this time period are that he formed a mercenary company and worked with them for some time, and he periodically came into contact with Stefan to threaten him and run him off (though it could be suggested that this was also Damon's love/hate way of checking up on Stefan). He grows in power, feeding on humans over the years, but no detail is provided otherwise. This aura of mystery adds to Damon's appeal, as fan speculation is one of the Vampire Diaries fandom's favored pastimes, and it is perhaps better not to know for certain.
In 1991, Damon ends up in the fictional town of Fell's Church, Virginia. He himself claims to've followed Stefan there to torment him, but it is later revealed that Katherine, who faked her own death and has really been alive all this time, lured both brothers there so that they'd meet Elena and feel guilty for the pain she feels they put her through. Damon competes with Stefan for Elena's affection, and also kills Mr. Tanner, the widely-hated history teacher, because Mr. Tanner pulls a knife on him while Damon's trying to feed on his blood. He is falsely accused of attacking Elena's fellow high schooler Vickie, and of leaving Stefan for dead in the well of an abandoned farm, and several other things, of which Katherine turns out to be ultimately guilty. In the final showdown with Katherine, Damon (like Stefan and Elena) is tied up in her secret hideout and is offered a second chance to rejoin her. He turns her down, though he does not offer a reason why. Along with Stefan, he watches Elena die, and both brothers promise her that they'll look out for one another.
Damon and Stefan live together in an uneasy truce for the next several months, until Bonnie's summoning spell calls Stefan back to Fell's Church to save them from a new evil. Damon tags along, claiming that some of his hair must've gotten mixed in with Stefan's and therefore he has to. The new evil turns out to be Klaus, the vampire who sired Katherine, come to get revenge for her death. Since Klaus is an Original, traditional means cannot destroy him. Like Katherine, Klaus also offers Damon a chance to get out of the way and join the winning side, and while Damon suggests that everybody do just that, he ends up defending Stefan in the end. Both brothers almost perish in the fight, but are saved thanks to Elena's spirit.
Elena and Stefan offer Damon a place with them, but Damon rejects that offer and heads off into the night.
Damon has the ability to turn into a crow or a wolf. He most frequently chooses his crow form, and especially likes to use this form to spy on people.
Damon can control the weather, as he does by keeping it cloudy for much of his stay in Fell's Church, since cloudy weather is easier on sensitive vampire eyes. Damon can also manipulate fog both indoors and out, as he creates a fog in the school gym when first appearing to Elena.
Damon has the usual vampire mind manipulation Powers. He can subtly manipulate humans into doing his bidding and he can telepathically communicate with other vampires. Damon also has the equally standard enhanced strength, stamina, dexterity and heightened senses that all vampires have.
Damon had a mother, a father, and has one brother, Stefan.
Damon's mother is deceased and unnamed in the books, and Stefan tells Elena that she passed away not long after giving birth to him, something he thinks Damon has always hated him for. He loved his mother very much.
Damon's father was Giuseppe, Conte di Salvatore. He and Damon had a contentious relationship in life, as Giuseppe felt that Damon was a ne'er-do-well who shirked his duties to the family, while Damon felt that his father was weak and let his other friends take advantage of his generosity, and would much rather be off having fun than following in those footsteps.
Damon's brother is Stefan Salvatore, and the only other "living" remnant of the Salvatore family. They were both turned into vampires at the same time, and have maintained the minimum required contact since then, seeing one another rarely in the five centuries of their vampire existence. They did not reunite until they both found themselves in Fell's Church.

Matt Honeycutt
Matt is tall and athletic, with blonde hair and blue eyes (Stefan observes that his eyes are open and honest). During the summer prior to The Awakening Matt helped out on his grandparents' farm, which gave him a tanned complexion.
He's described as being an attractive, wholesome, all-American, boy-next-door type. Certainly Elena still thinks that he's handsome, even after breaking up with him, and Bonnie shows some definite interest in him.
Due to his family being poor, he tends to wear older clothes, and Elena surmises at the beginning of The Awakening that his scuffed shoes must have been the same ones he had the previous year on account of not being able to afford new ones.
Despite being captain of the school football team, Matt is about as far from a stereotypical jock as you can get. He's fiercely loyal, and likes to see the best in people. When it comes to the subject of love and relationships, he's quite mature for his age. Despite being deeply in love with Elena, he is able to not only let her go as a girlfriend, but he's also able to remain her friend while not being bitter about his loss, coming to her aid several times (above and beyond the call of duty) in the story. Even more surprisingly, he's able to become best friends with Stefan, who by all rights should be considered his rival in his love for Elena.
He has faith in the basic goodness of people, and displays this several times during the course of the books, from sticking by Stefan despite damning evidence against him, to even managing to work out some motives for Damon's actions that prove him to be not quite as evil as he'd like people to believe. Indeed, the basic concept of vampires existing, while a shock, doesn't seem to bother him particularly. It's not that fact that Stefan is a vampire that sends him spiralling into denial in The Fury, but the fact that Stefan pretends to feel no remorse over attacking Tyler and his associates in the Quonset hut.
After the events of The Fury, Matt's faith in humanity and the world has been severely shaken, and he spends much of Dark Reunion in a previously uncharacteristic pessimistic and defeated state. It takes a renewal of friendship and a heart-to-heart with Stefan for him to start to regain some of his earlier determination and good humour.

Bonnie McCullough
Bonnie is short, with a heart-shaped face and wide, brown eyes. Her red hair is permed to curly during the books, and this is supposed to be a new look for her, one which she debuts on the first day of school in the first book.
Initially, Bonnie comes off as kind-hearted but not very bright at all. She starts off as the fickle, shallow, boy-obsessed, always-bubbly, insecure, slightly clueless friend. As the series goes on, however, Bonnie begins to develop, both as a person and as someone with psychic powers, and matures accordingly. She slowly realizes that she isn't as dumb as she believes herself to be (and, as a result, as she's convinced everyone else she is), and that she's useful, needed and loved by her friends.
Initially, Bonnie romanticizes death, especially her own, constantly talking about her Scottish grandmother's prophecy that she would be young and beautiful in her grave, and how romantically she might die. She is fickle in chasing after Stefan, then Matt, then Damon. By the end of the original series, however, Bonnie has become more grounded and serious, focusing on the problems at hand rather than on the boys at hand. She even surprises herself a few times with her own insightful, helpful contributions to the fight against Klaus.
Most of the time, Bonnie seems to act as an unwitting, unknowing medium for helpful spirits, most notably the spirit of Honoria Fell, who several times attempts to aid the girls through Bonnie. Bonnie does not remember anything she says or does while in this state. She also has occasional prophetic flashes, such as when she jokingly reads Elena's palm on the first day of school and comes up with a genuine prophecy.
In Dark Reunion, Bonnie begins to dabble in witchcraft, and successfully pulls off a summoning ritual to call Stefan back to Fell's Church, then successfully manages to help Stefan communicate with a ghostly Elena by various means. At the end of Dark Reunion, Bonnie is the one who screams about the unfairness of their tragic fate, which triggers Elena's return. It is unknown if Bonnie's powers played any role in making this happen, or if it was just a matter of lucky timing (it was the night of the summer solstice, when ghosts were said to be prone to returning to Earth anyway).
Bonnie has at least two older sisters. Mary, and another one who is in college. The phrasing 'one of Bonnie's sisters' makes it seem like more, as if it was Mary and one other sister, it would make sense to name her, or at least say 'Bonnie's other sister'.

Meredith Sulez
Meredith is tall, with an olive complexion, dark eyes, heavy black lashes, and loose black hair. According to Elena, she never wears make-up because she doesn't need any. She is described as very elegant and beautiful.
Calm and collected: Meredith seems to be one of the most sensible and grounded characters in the books and amongst Elena's friends and often comes across as "the voice of reason". She has a very wry personality, often making keen observations or (somewhat humorous) comments in a dry tone. She is normally very cool and unflappable, calm under pressure, and competent. She does things with minimal fuss, displaying grace, skill, and dignity. She is extremely cynical when it comes to vampires and the reason is suspected amongst fans to be because of the attack by Klaus on both her and her grandfather. She is also the only human female in the novel that seems to be completely unphased by Damon Salvatore and the only person that Damon admits to being afraid of.
It isn't entirely clear when Meredith's grandfather was attacked. In The Fury she states that it happened before she was born:
It happened a long time ago, before I was born. He wasn't badly hurt by it, but he never really got well. He became… well, sort of like Vickie, only more violent. It got so that they were afraid he'd harm himself, or somebody else. So they took him to a hospital, a place he'd be safe."
Yet in Dark Reunion she states he was attacked on her birthday, and that he then went on to attack her grandmother and herself.
My parents started celebrating it a week early because June 6 was too upsetting for them. It was the day my grandfather was attacked and went crazy." As Bonnie gasped, unable to speak, she added calmly, "He tried to kill my grandmother, you know. He tried to kill me, too."
Both of these stories contradict the other on several points.
Except for her grandfather, Meredith's family is rarely discussed in the books. It is unknown if she has any siblings. Both her parents and at least one grandmother are alive. Meredith's mother used to be friends with Caroline's mother a long time before the start of the series.
Meredith's grandfather currently resides in a mental institution in West Virginia. After the attack, Meredith's grandfather became a source of deep shame for the family. In Dark Reunion, Bonnie says that Meredith's parents "considered her grandfather's condition such a blot that they never allowed him to be mentioned to outsiders."

Alaric Saltzman
Alaric is good-looking with an athletic build, hazel eyes, and sandy brown hair (which he wears a little long). He has a boyish smile, and Elena observes that he's not really much older than the students in his class. Later on, in The Fury, Elena assesses him to be around four or five years older than she is, which would age him at around 23 years old at the top end. In Dark Reunion, Bonnie believes Alaric is 22.
Despite trying to appear as a fearsome vampire killer, he's really not a violent person, and can't stand to see innocents hurt. He even denies being a vampire hunter when Damon accuses him of it, and likely not just to save his own skin. Once it is established that Stefan is not the killer plaguing the town, Alaric is immediately concerned for his safety upon learning he's gone to meet with Caroline, where he will no doubt be ambushed.
He smiles a lot during The Struggle, having an easy-going nature, and a desire to connect with people. He's clearly not a teacher, falling back on what must be his own area of comfort to get to know the students and the potential killer among them by inviting them all to his place for a party. It's clear he feels comfortable around groups of people, and is able to function well as a host.
He's an experimental psychologist from Duke University, specialising in the research of psychic powers. His research took a sideways step upon the discovery of the victim of a vampire. He focused his research on vampire victims, becoming the foremost expert in the field

Aunt Judith
Judith is described as having a thin, mild face with flyaway hair. Her appearance isn't addressed much, though she seems to spend much of the series being flushed, worried or hurried.
Aunt and legal guardian of Elena and Margaret. She is a sister of their father, evidenced by the fact that Bonnie refers to her as 'Miss Gilbert' after she drops the girls off for the Founders' Day ceremony.
Engaged to Robert Maxwell. She marries and becomes Mrs. Maxwell by the time the graduation ceremony is held in Dark Reunion.


Margaret Gilbert
Margaret has blue eyes, white-blond or tow hair, and a high voice.
Margaret is generally cheerful, and she is empathetic enough to offer Elena some Halloween candy when her older sister seems distressed. She likes animals well enough to adopt a kitten, though unfortunately the kitten she chooses is an animal shape of Katherine von Swartzschild. Due to her age, she gives little to no evidence of ever truly understanding the activities and concerns of her older sister or the other characters. She perceives Elena’s death as her older sister’s having gone to be with their parents. In fact, given the ease with with she welcomes the vampire Elena's return, she does not seem to have understood that Elena is supposed to be dead even though she asks Elena if she has become an angel.
After Elena's death at the end of "The Fury," Margaret tells Bonnie that she's going to see Elena and her parents someday, but first she still had things to do. Bonnie thinks Margaret is smart for her age.
Margaret doesn't have much of a history as she's only approximately 4 years old. Elena and Margaret's parents died when she was around 1 year old, so she has little memory of them. It is unknown how she spends her time or if she has any friends, as the reader only sees her with Elena or Aunt Judith.

Mrs. Flowers
Mrs. Flowers is an old lady with grey hair and a smiling face. She's a small woman, and has bright, black eyes.
Mrs. Flowers comes across as a batty old lady, yet appearances can be deceiving. She has a wicked sense of humour, and seems to enjoy driving people insane wondering about what and who she is.
It's never actually confirmed in the original series just what Mrs. Flowers is, but Stefan observes early on in The Awakening that she seems to be more than she appears. She certainly seems to suspect (perhaps even know) what Stefan is. She makes knowing references about there being things lurking out in the woods, makes jokes about Stefan flying off the roof.The fact that the mirror is missing from Stefan's bathroom may also be a little joke on her part. Stefan himself reveals that vampires having no reflections is a myth, and there's no real reason for him to not have a mirror, especially given that he's quite fastidious about his appearance. It's easy to conclude this is Mrs. Flowers making another subtle hint that she knows what he is. She certainly makes no bones about knowing he's older than he appears by offering him some of her blackberry wine when the teenagers are only given grape juice. As far as she should be concerned, Stefan is the same age as the rest of them.
It is quite possible that she has some kind of psychic premonitions. On two occasions she was strangely absent from the Boarding House when by all rights she had every reason to be there. The first is on Halloween, when Elena discovers that Stefan is a vampire. It's as if she was deliberately keeping out of their way so that the necessary could take place. Again, after Stefan has been rescued from the well in The Struggle, she is absent from the Boarding House when they return with him, yet the doors are unlocked. This is something that Matt observes as very strange, and that you'd have to be crazy to leave your doors open like that given the recent spate of deaths. While she has her eccentricities, Mrs. Flowers is certainly not stupid, and it's possible that she knew they were coming, knew they wanted to do it as secretly as possible, and so paved the way for them while making herself scarce. It's also interesting to note that she may have had no problems leaving the doors unlocked as she knew the ones who were responsible couldn't get in without an invitation. In her mind, she was relatively safe.
In Nightfall, Mrs. Flowers reveals that she is a witch in the novel to Elena because she says that she's become unsociable in old age and mentions she had been a nurse because women were not encouraged to be doctors back when she was born. She admits to having a "soft spot" for Stefan. It is also noted that she is knowledgeable about herbs.
In "The Return: Nightfall" Mrs. Flowers reveals to Elena that she became a nurse when she was younger (though she wanted to be a doctor) because women back then were discouraged from becoming doctors. She then confirms everyone's suspicions about her by stating that she is a witch (and that she finds it to be a pain) and has known about Stefan all along. She tells Elena that she has a "soft spot" for him and has decided to help Elena find Stefan, who has gone missing. She helps cure Matt and it is noted that she's educated in herbology. She tells Bonnie and Meredith that her mother died sometime back in 1901 and that she (Mrs. Flowers) used to be a medium on vaudeville.

Katherine von Swartzschild
Katherine looks almost exactly like Elena, with jewel-blue eyes, golden blonde hair, and pale skin. There are however a few slight differences between the two girls. Katherine is shorter, her eyes are wider and more blue, and her hair is a few shades darker than Elena's. Katherine also has "almost silvery" eyebrows and eyelashes. She is, of course, very beautiful.
At first, Katherine is described through flashbacks of memory. She finally makes her appearance in The Fury. She looks the same, except for her long, golden hair, which has grown past floor-length and now trails behind her; Elena initially mistakes it for a train on her gown. Her face is also described (by Elena) simply as looking "wrong" and "distorted," twisted by hunger and mocking.
When the Salvatore brothers first meet Katherine during the Renaissance, she is a fragile young German noblewoman with a dark secret. Katherine is soft-spoken, innocent, and excessively naïve. In spite of her vampirism, she does not appear to understand shadow emotions and the darker side of life, and as such she fails to grasp the deep roots of the conflict between Stefan and Damon. She displays her childishness by refusing to choose between the two brothers and believing that martyring herself will resolve their difficulties.
In the centuries between the Italian Renaissance and the time of The Fury, Katherine has grown quite insane, which is at least partly attributable to the influence of Klaus. She is jealous of Elena and hates Damon and Stefan for daring to pursue another woman. She boasts about killing many humans and vampires over the past few centuries, and has become hungry for power and revenge.
Born in Germany in the 1500s to the Baron von Swartzschild, Katherine was frail during her childhood and her last illness was terminal. She recalls later that she was unable to breathe and too weak to move; her father was devastated. Gudren, her maid, sought out a vampire namedKlaus who was in the local village at the time, and he made her into a vampire, saving her from death and making her much stronger than she had been in life. It is Gudren who advises her on the practicalities of being a vampire, telling her to have a lapis lazuli ring made as a talisman against the sun, and bringing her possets and small animals for feeding.
Sometime after this her father brings her to Italy during the summer, as he believes the warmer climate will help her recover. He is likely an old friend of the Conte di Salvatore, as he stays with him and leaves Katherine at the estate when he has business in Florence. It is here that she meets the Conte's younger son Stefan Salvatore and the two begin a courtship; she shares her secret with him. They like each other enough that their fathers begin speaking of marriage.
During her stay at the Salvatore estate, it is noted that she only leaves her chamber at twilight, but Conte Giuseppe overlooks this odd behaviour due to Katherine's overwhelmingly sweet personality. She tells Stefan that she does not drink human blood because she does not desire power; for the same reason despite Klaus' offers, she has not exchanged blood with him since her initial transformation. She believes that drinking human blood should not be done lightly, and she wants to wait until she has found an eternal companion.
Damon's return from the university halts any talk of marriage, as Katherine is also drawn to his darkly seductive charm. When she intervenes in an argument between Damon and his father which would probably otherwise result in Damon being cut off from his inheritance, Stefan becomes jealous and the pre-existing tension between the brothers mounts. As summer begins to draw to a close, Damon notes that the Baron will soon leave Florence with Katherine, unless she chooses to marry and remain there. He also reveals that Katherine has shared her secret with him, intensifying Stefan's resentment. The brothers begin to fight for her affection in earnest, but Katherine reminds them that she is a vampire and cannot live like a normal Florentine lady, and declares that her husband must renounce ordinary human life for the shadows. Since this does not deter either of them she tells them that she needs time to choose.
Katherine makes her choice by coming to them both separately during the night and exchanging blood with both, turning them into vampires, declaring that she wants the three of them to be 'joyous companions, forever'. Both brothers vehemently reject her decision, furious with jealousy and wounded pride. Katherine runs away from them in tears. She conceives a plan with Gudren's help that she believes will make Damon and Stefan put aside their hatred and realise their error: she fakes her own death. The next morning the brothers find what they believe to be Katherine's ashes and clothes beneath her favourite lemon tree. They blame each other for her death, fetch their swords and kill each other, waking up later in the family crypt as vampires. Meanwhile Katherine goes back to the German village to find Klaus, with whom she lives for centuries. The books suggest that he abuses her while teaching her to become a stronger vampire, and over time she becomes power-hungry and insane, losing utterly her childlike innocence and naïveté. She eventually attempts to kill Klaus, evidently believing that she has succeeded.
At some point during the late twentieth century she comes to the American town of Fell's Church, where she sees Elena Gilbert, who bears a striking resemblance to her; Katherine considers that she may even be a very distant relative. She subliminally influences Stefan and Damon to follow her to the town, hoping that they will see Elena, honour her memory and feel remorse for the events of centuries ago. However, Stefan falls in love with Elena and Damon tries to seduce her.
Katherine masquerades as a white kitten which Elena's little sister Margaret takes as a pet; at times she acts antagonistically towards the brothers, as when she traps Stefan in a well and has serious thoughts about wringing Damon's neck while he is in crow form -- a dream whichBonnie McCullough telepathically picks up on. When Stefan proposes to Elena and gives her the ring that belonged to Katherine, the latter becomes enraged and drives Elena's car into the river, killing her. After Elena awakens as a vampire, Katherine disturbs Elena's memorial service, influencing the town's dogs to attack their owners outside the church. This event causes Elena, Stefan and Damon to realise that something is amiss; they begin searching for the 'Other Power' in Fell's Church, which leads them to a deadly confrontation with Katherine in the tomb of Honoria Fell where she has taken up residence, and attacks them in the form of a snow-white tiger.
Katherine ties them up, tortures them a little and finally reveals herself to the trio, taunting them with the details of her antics in Fell's Church, of which they had been unaware. Meanwhile she directs the dogs to attack students leaving the Snow Dance at Elena's high school. As she plots to kill them, Elena outwits her by lunging at her and removing her lapis lazuli necklace, causing her to burn up in the sunlight, turning the centuries-old lie into truth and saving the townspeople as well as Stefan and Damon.
In Dark Reunion, Klaus arrives in Fell's Church seeking revenge for Katherine's death.
By the time of The Fury, Katherine has become a powerful vampire. She can shapeshift into three forms: tiger, owl, and kitten. She has some control over the weather. Katherine can also appear in people's dreams, and can subliminally influence them to do her bidding.
As a human and young vampire, Katherine was very close to her father, and she was upset at the thought of leaving him. Her close relationship with Gudren, her maid, is evident in the fact that it was Gudren who arranged for Katherine to be changed into a vampire by Klaus. After her faked death, Katherine stayed with Klaus for centuries. She says in The Fury that she eventually killed Klaus, although this claim is proven false by Klaus's appearance in Dark Reunion.
During the Italian Renaissance, Katherine fell in love with both Damon and Stefan Salvatore. Her refusal to choose between them led to her faked suicide, after which the brothers killed each other and became vampires. Katherine reveals in The Fury that she always loved Stefan more than Damon.

Klaus
Klaus is very Nordic in appearance, with electric blue eyes and short, close-cropped platinum blond hair. He is described as being handsome despite the fact that his features are often contorted in madness. He wears a dusty long tan coat.
Klaus is extremely deranged, and the line between his evil and his madness is very blurry. When pressed, he is deadly serious and reminds everyone about his unfathomable old age, but most of the time he seems unnaturally chipper, and his evil deeds during Dark Reunion are always tinged with irony. He refers to everyone as "sport," he writes "Goodnight, sweetheart" on Vickie's mirror after brutally murdering her and leaving that same song playing in her room, and he kills (or nearly kills) Stefan with the same white ash wood spear that was intended for him. His mood changes from cheerful and amused to absolutely enraged in seconds, and he is very unpredictable. Despite his seemingly erratic and scattered personality, he seems to be a patient and methodical killer capable of elaborate plans.

"[...]I've been around a long time."

"How long?" said Stefan, unimpressed.

"A long time..." The blond man's gaze turned dreamy, as if looking back over the years. "I was tearing pretty white throats when your ancestors were building the Colosseum. I killed with Alexander's army. I fought in the Trojan War. I'm old, Salvatore. I'm one of the Originals. In my earliest memories I carried a bronze axe."
[...]

"I helped bring the Roman Empire down," the blond man continued dreamily. "They called us barbarians - they just didn't understand! War, Salvatore! There's nothing like it. Europe was exciting back then. I decided to stick around the countryside and enjoy myself."

- Dark Reunion, p. 197

There's even less known about Klaus' history than Damon or Katherine's. Pretty much the only known points of Klaus' life are those listed above, and the points where his timeline intersects Katherine's. So, to summarize...
Klaus is of unknown age, but is at least from the bronze age. He seems to have fought in every major war through time, most notably in Alexander the Great's army, in the Trojan War, and in the wars that led to the Roman Empire's downfall (on the Germanic side). He then decided to stick around the general area of Germany where, sometime in the 15th century, he turned a dying young Katherine into a vampire and then left her to her own devices.
Nothing more is known about Klaus' whereabouts since then, except that he spent a lot of time with Katherine after she ran away from the Salvatore brothers, and that she believed that she had killed him at some point. He may have been the vampire who attacked Meredith's grandfather, or he may have simply manipulated Meredith's grandfather to mislead the cast of Dark Reunion. His vernacular suggests that he's spent a lot of time in modern America, though - certainly enough to pick up slang like "sport" and use it comfortably and casually, and know (and use with effective irony) the song Goodnight, Sweetheart.
Klaus arrives in Fell's Church in 1992, where he somehow comes in contact with Tyler and helps him become a werewolf. After that, he uses Tyler and his own enhanced vampire powers to play with the Salvatore brothers, and their human friends. He murders Vickie in an extremely violent manner and offers Damon a truce if he'll keep out of his way while he kills Stefan. Klaus also kidnaps Caroline and holds her hostage as bait to get Stefan to fight him.
In the final showdown against everyone, all of the weapons used against him fail, Klaus more or less kills Stefan, and nearly kills Damon as well, until an intervention from Elena's spirit, leading an army's worth of unquiet Civil War ghosts (the site of their battle was also the site of a bloody Civil War battle) against him. The ghosts carry a screaming Klaus away, and his current whereabouts (and state of being) are unknown.

Caroline Forbes
Caroline is described as tall, curvaceous and bronzed, like a Vogue model. She has wavy auburn hair and catlike, slanted, bright green eyes. She frequently wears skimpy clothing that emphasizes her assets, and is always perfectly coiffed.
Caroline's personality is difficult to ascertain, as we mostly only see her being adversarial to Elena. Elena notes that she and Caroline used to be the best of friends, though they developed a healthy rivalry for social status in their social group and at their school. At some point over the summer while Elena was in France, Caroline turned on her for reasons unknown to Elena (and thus unknown to the reader), and when Elena returns on the first day of school, she is met with a surprisingly cold reception from her former friend.
Caroline is extremely competitive, and seems to be willing to do anything to get what she wants, regardless of legal or ethical implications. She takes social slights very personally, and seems to value social status above most other things. After Elena's second and then-final death, Caroline seems to have a change of heart; she rejoins her old friends, Bonnie and Meredith, and stops speaking ill of Elena.
She is also manipulative, cunning, and selfish doing everything in her power to get what she wants.

Tyler Smallwood
Tyler is the school bully, usually seen hanging around with his best buddy Dick Carter, or getting up to things with Caroline in convenient corners. He’s on the school football team and, being the thug he is, takes it upon himself to try and torment Stefan from day one. However, when Stefan thwarts his attack on Elena in the graveyard and causes him some painful physical damage, his antagonistic attitude turns to one of outright hostility, and he’s determined to make Stefan pay for what he’s done. In Dark Reunion, it transpires that there’s a reason for his animal-like personality and behaviour; he discovers that he has werewolf blood, and with the help of Klaus and Sue Carson’s death, he activates that blood and actually becomes a werewolf.

Vickie Bennett
Vickie is one of the most tragic characters in the book. Not too bright to begin with, she’s attacked by Katherine and left traumatised and in need of therapy, which doesn’t seem to do her much good. As if that wasn’t bad enough, Katherine has some control of the girl’s mind and uses as her puppet for her own amusement. Before she has barely any time to try and get herself sorted out, she’s plunged back into a bad mental place in the events of Dark Reunion, after which she is eventually killed by Klaus.