The youngest of three children, Toussaint was born in 1938 in New Orleans and grew up in a shotgun house in the Gert Town neighborhood, where his mother, Naomi Neville (whose name he later adopted pseudonymously for some of his works), welcomed and fed all manner of musicians as they practiced and recorded with her son. His father, Clarence, worked on the railway and played trumpet. Allen Toussaint learned piano as a child and took informal music lessons from an elderly neighbor, Ernest Pinn. In his teens he played in a band, the Flamingos, with the guitarist Snooks Eaglin, before dropping out of school. A significant early influence on Toussaint was the syncopated "second-line" piano style of Professor Longhair.  After a lucky break at age 17, in which he stood in for Huey "Piano" Smith at a performance with Earl King's band in Prichard, Alabama, Toussaint was introduced to a group of local musicians led by Dave Bartholomew, who performed regularly at the Dew Drop Inn, a nightclub on Lasalle Street in Uptown New Orleans. His first recording was in 1957 as a stand-in for Fats Domino on Domino's record "I Want You to Know", on which Toussaint played piano and Domino overdubbed his vocals. His first success as a producer also came in 1957 with Lee Allen's "Walking with Mr. Lee". He began performing regularly in Bartholomew's band, and he recorded with Fats Domino, Smiley Lewis, Lee Allen and other leading New Orleans performers.  After being spotted as a sideman by the A&R man Danny Kessler, he initially recorded for RCA Records as Al Tousan. In early 1958 he recorded an album of instrumentals, The Wild Sound of New Orleans, with a band including Alvin "Red" Tyler (baritone sax), either Nat Perrilliat or Lee Allen (tenor sax), either Justin Adams or Roy Montrell (guitar), Frank Fields (bass), and Charles "Hungry" Williams (drums). The recordings included Toussaint and Tyler's composition "Java", which first charted for Floyd Cramer in 1962 and became a number 4 pop hit for Al Hirt (also on RCA) in 1964. Toussaint also recorded and co-wrote songs with Allen Orange in the early 1960s.

Answer this question "How did his career start?" by extracting the answer from the text above.
After a lucky break at age 17, in which he stood in for Huey "Piano" Smith at a performance with Earl King's band in Prichard, Alabama,