Rubeus Hagrid was born to a giantess and a wizard. Although his mother left at a young age, Hagrid was raised by his father and started Hogwarts in 1940. He was sorted into Gryffindor and had an instant attraction to trouble, especially in the shape of creatures. During Hagrid's third year at Hogwarts, a young Tom Riddle took advantage of this fact, and framed Hagrid for the attacks from the Chamber of Secrets opening the first time, resulting in Hagrid being expelled from the school and his wand being snapped.

Albus Dumbledore didn't believe Hagrid was to blame, and he spoke up for him. Hagrid was able to be trained as the school's Groundskeeper, and later became the Keeper of the Keys as well. Due to this, Hagrid had the deepest of loyalties to Albus Dumbledore and joined both the first and second wars as part of the Order of the Phoenix. Hagrid may not have been the strongest wizard on the field, but he remained brave and loyal through the entire fight.

He was still employed at the castle in 2017, and even got to meet Harry and Ginny's oldest son.

Rubeus Hagrid was born to Fridwulfa (a giantess) and Mr Hagrid (a wizard) on 6th December 1928. Hagrid had very few memories of his mother as she left home when he was only 3 years old due to his small size. Fridwulfa rejoined her Giant colony instead, breaking Mr Hagrid's heart in the process. Hagrid grew up with his father near the Forest of Dean, in the West Country of England.

Mr Hagrid was a very small human, and could easily be picked up by Rubeus by the time his son was age 6. Mr Hagrid was overjoyed at his son being accepted to Hogwarts.

Rubeus Hagrid was sorted into Gryffindor House in 1940. By the time he was finishing his second year, Hagrid had lost his father. During Hagrid's third year at the school, the Chamber of Secrets was opened by a young Tom Riddle (a fifth-year student at the time), and his monster was attacking muggle-born students at his command. Upon the death of Myrtle Warren, the school was faced with closure, which Riddle was against allowing to happen. Rather than confessing to the crimes, Riddle knew of Hagrid's love of dangerous creatures. Exposing Hagrid's latest find - a young acromantula which Hagrid called Aragog - the attacks were ultimately blamed on Rubeus Hagrid's creature. Aragog managed to escape to the Forbidden Forest, but Hagrid was expelled as a punishment. As a result, his wand was also snapped to prevent him from casting magic.

At this point, Albus Dumbledore was a Professor for Transfiguration at the school, but he still spoke out for Hagrid. In the end, he was able to get Headmaster Dippet to agree for Hagrid to remain in residence at the school and to be trained as the school Gamekeeper.

Rubeus Hagrid remained deeply loyal to Albus Dumbledore. He joined the first and second wizarding wars as part of the Order of the Phoenix. In the first wizarding war, he was tasked with the retrieval of infant Harry Potter after Lord Voldemort's attack on Lily and James Potter. Hagrid safely delivered Harry Potter to the Dursleys in Privet Drive. Hagrid returned for Harry Potter in 1991, on the boy's 11th birthday, to collect him for starting Hogwarts.

In 1995-96 following the reappearance of Lord Voldemort during the Triwizard Tournament, Rubeus Hagrid was assigned to seek out the giant colony in Minsk in a bid to gain their loyalty in the predicted upcoming war. Hagrid's talks with the giants were unsuccessful, as the Death Eaters had already won them over.

Rubeus Hagrid was one of Alastor Moody’s Advanced Guard, tasked with moving Harry Potter the night he turned seventeen. The flying motorbike Hagrid and Harry were on was attacked mid-flight, but both survived, though others were lost and injured as a result of the mission.

Hagrid remained at Hogwarts during Severus Snape's time as Headmaster. He was placed in charge of detention for students, but he eventually went into hiding with his giant half-brother, Grawp. Hagrid returned for the Final Battle. He was the first to congratulate Harry Potter after the war was over.

Hagrid was still in employment at Hogwarts School of Witchcraft and Wizardry in 2017 (age 89), where he met the son of Harry and Ginny, Albus Potter.