Armstrong often stated that he was born on July 4, 1900.
Borrowing his stepfather's gun without permission, he fired a blank into the air and was arrested on December 31, 1912. He spent the night at New Orleans Juvenile Court, then was sentenced the next day to detention at the Colored Waif's Home.
On June 14, 1914, Armstrong was released into the custody of his father and his new stepmother, Gertrude. He lived in this household with two stepbrothers for several months. After Gertrude gave birth to a daughter, Armstrong's father never welcomed him, so he returned to his mother, Mary Albert. In her small home, he had to share a bed with his mother and sister.
Armstrong played in brass bands and riverboats in New Orleans, first on an excursion boat in September 1918.
In 1919, Oliver (was an American jazz cornet player and bandleader) decided to go north and resigned his position in Kid Ory's band; Armstrong replaced him. He also became the second trumpet for the Tuxedo Brass Band.
In 1922, he moved to Chicago at the invitation of King Oliver. With Oliver's Creole Jazz Band he could make enough money to quit his day jobs. Although race relations were poor, Chicago was booming. The city had jobs for blacks making good wages at factories with some leftover for entertainment.
His first studio recordings were with Oliver for Gennett Records on April 5–6, 1923.
Armstrong and Oliver parted amicably in 1924.
On February 4, 1924, he married Lil Hardin Armstrong, King Oliver's pianist, divorced in 1938.
In 1925, Armstrong returned to Chicago largely at the insistence of Lil, who wanted to expand his career and his income.
Armstrong returned to New York in 1929, where he played in the pit orchestra for the musical Hot Chocolates, an all-black revue written by Andy Razaf and pianist Fats Waller. He also made a cameo appearance as a vocalist, regularly stealing the show with his rendition of "Ain't Misbehavin'".
Louis then married Lucille Wilson on October 1942, a singer at the Cotton Club, to whom he was married until his death in 1971.
Armstrong was featured as a guest artist with Lionel Hampton's band at the famed second Cavalcade of Jazz concert held at Wrigley Field in Los Angeles which was produced by Leon Hefflin Sr. on October 12, 1946.
Following a highly successful small-group jazz concert at New York Town Hall on May 17, 1947, featuring Armstrong with trombonist/singer Jack Teagarden, Armstrong's manager, Joe Glaser dissolved the Armstrong big band on August 13, 1947, and established a six-piece traditional jazz group featuring Armstrong with (initially) Teagarden, Earl Hines and other top swing and Dixieland musicians, most of whom were previously leaders of big bands. The new group was announced at the opening of Billy Berg's Supper Club.
He was the first jazz musician to appear on the cover of Time magazine, on February 21, 1949.
In June 1950, Suzy Delair performed rehearsals of the song "C'est si bon" with Aimé Barelli and his Orchestra at the Monte Carlo casino where Louis Armstrong was finishing the evening. Armstrong enjoyed the song and he recorded the American version in New York City on June 26, 1950.
Louis Armstrong and his All Stars were featured at the ninth Cavalcade of Jazz concert also at Wrigley Field in Los Angeles produced by Leon Hefflin Sr. held on June 7, 1953 along with Shorty Rogers, Roy Brown, Don Tosti and His Mexican Jazzmen, Earl Bostic, and Nat "King" Cole.
Against his doctor's advice, Armstrong played a two-week engagement in March 1971 at the Waldorf-Astoria's Empire Room. At the end of it he was hospitalized for a heart attack. He was released from the hospital in May, and quickly resumed practicing his trumpet playing. Still hoping to get back on the road, Armstrong died of a heart attack in his sleep on July 6, 1971, a month before his 70th birthday.