Arnold Jacob Auerbach was one of the four children of Marie and Hyman Auerbach. Hyman was a Russian-Jewish immigrant from Minsk, Russia, and Marie Auerbach, nee Thompson, was American-born. Auerbach Sr. had left Russia when he was 13, and the couple owned a delicatessen store and later went into the dry-cleaning business. Little Arnold spent his whole childhood in Williamsburg, Brooklyn, playing basketball.

In 1941, Auerbach began coaching basketball at the St. Albans School and Roosevelt High School in Washington, D.C. Two years later, he joined the US Navy for three years, coaching the Navy basketball team in Norfolk. There, he caught the eye of Washington millionaire Mike Uline, who hired him to coach the Washington Capitols in the newly founded Basketball Association of America (BAA), a predecessor of the NBA.  In the 1946-47 BAA season, Auerbach led a fast break-oriented team built around early BAA star Bones McKinney and various ex-Navy players to a 49-11 win-loss record, including a standard-setting 17-game winning streak that stood as the single-season league record until 1969. In the playoffs, however, they were defeated by the Chicago Stags in six games.  The next year the Capitols went 28-20 but were eliminated from the playoffs in a one-game Western Division tie-breaker. In the 1948-49 BAA season, the Caps won their first 15 games and finished the season at 38-22. The team reached the BAA Finals, but were beaten by the Minneapolis Lakers, who were led by Hall-of-Fame center George Mikan. In the next season, the BAA and the rival league National Basketball League merged to become the NBA, and Auerbach felt he had to rebuild his squad. However, owner Uline declined his proposals, and Auerbach resigned.  After leaving the Capitols, Auerbach became assistant coach of the Duke Blue Devils men's basketball team. It was assumed that Auerbach would take over for head coach Gerry Gerard, who was battling cancer. During his tenure at Duke, Auerbach regularly worked with future All-American Dick Groat. Auerbach later wrote that he "felt pretty bad waiting for [Gerard] to die" and that it was "no way to get a job".  Auerbach left Duke after a few months when Ben Kerner, owner of the Tri-Cities Blackhawks, gave him the green light to rebuild the team from scratch. Auerbach traded more than two dozen players in just six weeks, and the revamped Blackhawks improved, but ended the 1949-50 NBA season with a losing record of 28-29. When Kerner traded Auerbach's favorite player John Mahnken, an angry Auerbach resigned again.

How did his team do?