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Early life and adolescence

Kerouac was born on March 12, 1922, in Lowell, Massachusetts, to French Canadian parents, Léo-Alcide Kéroack (1889–1946) and Gabrielle-Ange Lévesque (1895–1973).

There is some confusion surrounding his name, partly because of variations on the spelling of Kerouac, and because of Kerouac's own statement of his name as Jean-Louis Lebris de Kerouac. His reason for that statement seems to be linked to an old family legend that the Kerouacs had descended from Baron François Louis Alexandre Lebris de Kerouac. Kerouac's baptism certificate lists his name simply as Jean Louis Kirouac, the most common spelling of the name in Quebec. Kerouac's roots were indeed in Brittany, and he was descended from a middle-class merchant colonist, Urbain-François Le Bihan, Sieur de Kervoac, whose sons married French Canadians.

Kerouac's father Leo had been born into a family of potato farmers in the village of Saint-Hubert-de-Rivière-du-Loup, Quebec. Jack also had various stories on the etymology of his surname, usually tracing it to Irish, Breton, Cornish, or other Celtic roots. In one interview he claimed it was from the name of the Cornish language (Kernewek), and that the Kerouacs had fled from Cornwall to Brittany. Another version was that the Kerouacs had come to Cornwall from Ireland before the time of Christ and the name meant "language of the house". In still another interview he said it was an Irish word for "language of the water" and related to Kerwick. Kerouac, derived from Kervoach, is the name of a town in Brittany in Lanmeur, near Morlaix.

Jack Kerouac later referred to 34 Beaulieu Street as "sad Beaulieu". The Kerouac family was living there in 1926 when Jack's older brother Gerard died of rheumatic fever, aged nine. This deeply affected four-year-old Jack, who later said Gerard followed him in life as a guardian angel. This is the Gerard of Kerouac's novel Visions of Gerard. He had one other sibling, an older sister named Caroline. Kerouac was referred to as Ti Jean or little John around the house during his childhood.

Kerouac spoke French with his family and began learning English at school, around age six; he began speaking it confidently in his late teens. He was a serious child who was devoted to his mother, who played an important role in his life. She was a devout Catholic, who instilled this deep faith into both her sons. He later said she was the only woman he ever loved. After Gerard died, his mother sought solace in her faith, while his father abandoned it, wallowing in drinking, gambling, and smoking.

Some of Kerouac's poetry was written in French, and in letters written to friend Allen Ginsberg towards the end of his life, he expressed a desire to speak his parents' native tongue again. In 2016, a whole volume of previously unpublished works originally written in French by Kerouac was published as La vie est d'hommage.

On May 17, 1928, while six years old, Kerouac made his first Confession. For penance, he was told to say a rosary, during which he heard God tell him that he had a good soul, that he would suffer in life and die in pain and horror, but would in the end receive salvation. This experience, along with his dying brother's vision of the Virgin Mary (as the nuns fawned over him, convinced he was a saint), combined with a later study of Buddhism and an ongoing commitment to Christ, solidified the worldview which informed his work.

Kerouac once told Ted Berrigan, in an interview for The Paris Review, of an incident in the 1940s in which his mother and father were walking together in a Jewish neighborhood on the Lower East Side of New York. He recalled "a whole bunch of rabbis walking arm in arm... teedah- teedah – teedah... and they wouldn't part for this Christian man and his wife, so my father went POOM! and knocked a rabbi right in the gutter." Leo, after the death of his child, also treated a priest with similar contempt, angrily throwing him out of the house despite his invitation from Gabrielle.

Kerouac was a capable athlete in football and wrestling. Kerouac's skills as running back in football for Lowell High School earned him scholarship offers from Boston College, Notre Dame, and Columbia University, where he enrolled in 1940.

From around this time, Kerouac's journal includes an ambitious "Immediate Reading List," a wide-ranging list that includes sacred texts from India and China as well as a note to read " Emerson and Thoreau (again)."

He spent a year at Horace Mann School, where he befriended Seymour Wyse, an Englishman whom he later featured as a character, under the pseudonym 'Lionel Smart', in several of Kerouac's books. He also cites Wyse as the person who introduced him to the new styles of jazz, including bop. After his year at Horace Mann, Kerouac earned the requisite grades for entry to Columbia. Kerouac broke a leg playing football during his freshman season, and during an abbreviated second year he argued constantly with coach Lou Little, who kept him benched. While at Columbia, Kerouac wrote several sports articles for the student newspaper, the Columbia Daily Spectator, and joined the Phi Gamma Delta fraternity. He was a resident of Livingston Hall and Hartley Hall, where other Beat Generation figures lived. He also studied at The New School.