The Basketball Association of America was founded in 1946 by owners of the major ice hockey arenas in the Northeastern and Midwestern United States and Canada. On November 1, 1946, in Toronto, Ontario, Canada, the Toronto Huskies hosted the New York Knickerbockers at Maple Leaf Gardens, in a game the NBA now refers to as the first game played in NBA history. The first basket was made by Ossie Schectman of the Knickerbockers. Although there had been earlier attempts at professional basketball leagues, including the American Basketball League (ABL) and the NBL, the BAA was the first league to attempt to play primarily in large arenas in major cities. During its early years, the quality of play in the BAA was not significantly better than in competing leagues or among leading independent clubs such as the Harlem Globetrotters. For instance, the 1948 ABL finalist Baltimore Bullets moved to the BAA and won that league's 1948 title, and the 1948 NBL champion Minneapolis Lakers won the 1949 BAA title. Prior to the 1948–49 season, however, NBL teams from Fort Wayne, Indianapolis, Minneapolis, and Rochester jumped to the BAA, which established the BAA as the league of choice for collegians looking to turn professional.

On August 3, 1949, the remaining NBL teams–Syracuse, Anderson, Tri-Cities, Sheboygan, Denver, and Waterloo–merged into the BAA. In deference to the merger and to avoid possible legal complications, the league name was changed to the present National Basketball Association, even though the merged league retained the BAA's governing body, including Maurice Podoloff as president. To this day, the NBA claims the BAA's history as its own. It now reckons the arrival of the NBL teams as an expansion, not a merger, and does not recognize NBL records and statistics.
Tell me about the history of how the NBA started?
The league was founded in New York City on June 6, 1946, as the Basketball Association of America (BAA). It changed its name to the National Basketball Association on August 3, 1949, after merging with the competing National Basketball League..