Vincent Crabbe (1979 or 1980 – 2 May, 1998) was a pure-blood Dark Wizard, and the son of Death Eater Crabbe Sr.. Vincent Crabbe was also a student at Hogwarts and a member of Slytherin House. Crabbe, and Gregory Goyle were rarely seen without their ringleader Draco Malfoy. While Dolores Umbridge was Headmistress, he joined the Inquisitorial Squad. In his last year at Hogwarts, he became a Dark Wizard, as he learned to cast powerful dark curses, such as the Killing and the Cruciatus Curse. He accidentally killed himself using Fiendfyre on 2 May 1998, during the Battle of Hogwarts.
Vincent Crabbe was born into the pure-blood Crabbe family. His father, Mr. Crabbe, was a Death Eater. This likely influenced his son's prejudice against Muggle-borns and other non pure-bloods.
At the start of his first year, Crabbe was sorted into Slytherin House, along with his friends Draco Malfoy and Gregory Goyle, both of whom were also the sons of Death Eaters. Harry Potter noticed that Crabbe and Goyle seemed to act as bodyguards for Malfoy. When Draco challenged Harry to a duel, he selected Crabbe as his Second, although the challenge was merely a ruse to get Harry in trouble for being out of bed after hours.
During the second opening of the Chamber of Secrets, Harry Potter, Ron Weasley, and Hermione Granger tricked him and Goyle into eating cakes containing a sleeping draught — by leaving the cakes on a banister, even though Crabbe and Goyle had already eaten much more than their fill (which would explain his obesity). Ron and Harry used hairs from Crabbe and Goyle to impersonate them, as components of a Polyjuice Potion, and spy on Malfoy in the Slytherin Common Room (Hermione did not go as Millicent Bulstrode because she had used cat hairs, thinking they were Millicent's hairs from her robes, transforming her partly into a cat).
On the way to Hogwarts on his third year of education, Crabbe along with his friends stepped into Harry Potter's compartment to bully him. However, they could not act on their wishes as the new Defence Against the Dark Arts professor, Remus Lupin, was in the compartment, sleeping. Early in the school year it was quite clear that the Dementors guarding Hogwarts from Sirius Black were feared by Harry, and so during a Quidditch match, Crabbe and his friends put their cloaks up and pretended to be Dementors in an attempt to scare Harry, which it did and Harry cast a Patronus charm in response. Goyle was later humiliated when Harry (under his Invisibility cloak) defended his friends Hermione Granger and Ron Weasley by throwing snowballs at him. Crabbe's attempts to scare Harry later in the year were foiled, as he had too much protection from students and staff.
In the 1994-1995 school year, the Triwizard Tournament was held at Hogwarts school. After Harry Potter became a champion alongside Cedric Diggory, Crabbe, Goyle and Malfoy passed out badges that could be made to read Potter Stinks, and taunted Harry regularly, such as commenting that he was betting Harry wouldn't last more than a few minutes with the dragons. At the end of the year, Harry was almost killed by Lord Voldemort, and saw that Crabbe's father was a Death Eater.
In their fifth year, Crabbe and Goyle each became Beaters for the Slytherin Quidditch team. During the Slytherin vs. Gryffindor Quidditch match, Crabbe sent a Bludger at Harry, angry because he caught the Snitch before Draco (the Seeker then) did. Harry got into a fight alongside George Weasley and got a lifetime ban from Quidditch, courtesy of Dolores Umbridge.