High Quality Content by WIKIPEDIA articles! The 1957 NBA Playoffs was the postseason tournament of the National Basketball Association`s 1956-1957 season. The tournament concluded with the Eastern Division champion Boston Celtics defeating the Western Division champion St. Louis Hawks, four games to three in the NBA Finals. It was the first championship in Celtics history; as of 2009 the Celtics lead the league in NBA titles won, with 17.