In 1947, the Basketball Association of America, a league of eleven professional basketball teams, including the Boston Celtics and New York Knicks, hosted the first professional basketball finals, between the Chicago Stags of its Western Division and the Philadelphia Warriors of its East Division. The Warriors won that first basketball Finals championship. In 1949, the Basketball Association of America officially merged with the National Basketball League to form the current professional basketball league, the National Basketball Association of America, then a seventeen-team league after the merger. However, the first NBA Finals had taken place in 1947, with the Chicago Stags playing the Philadelphia Warriors, the latter being the winners that year.
Until 1949, the playoffs (then the BAA Finals) were run as a three-stage tournament in which the two winners of the semifinal rounds competed against each other in a final round. In 1950, the Western Division champions and the Central Division champions played each other, with the winner between the two playing the Eastern Division champions. Beginning in 1951, each year the NBA Finals have been held as a best-of-seven championship series between the Eastern Conference champions against the Western Conference champions at the end of the basketball postseason, and the winning team becomes the recipient of a Larry O’Brien Championship Trophy to display the sporting award prominently in their home stadium.
Between the Eastern Conference and the Western Conference, the Eastern Conference has won the most play-off series in the history of the competition, with thirty-five wins compared to twenty-eight for the Western Conference. (During his time, the Central Division won a championship.)
Beginning in 1985, the finals have extended home court advantage to the team entering the playoffs with a better season by having the first two games at their home stadium, as well as the final two if those games are played. Prior to that, most years were played on the home court of the team with the best season record at the start of the playoffs for the first two games, then games five and seven if necessary. (The final tiebreaker played with that host format was the legendary 1984 matchup between the rival Boston Celtics and Los Angeles Lakers, the first time those teams met on the court for the finals since 1969, with the Celtics emerging as the 1984 victors AND the 1985 Finals between them, which the Lakers won that year, marked the first time the current host format was employed).
Celtics coach Red Auerbach suggested the new lodging format to NBA Commissioner David Stern, noting that it would reduce the frequency of such long trips between East and West Coast cities; however, he later regretted making the suggestion, realizing that the change actually meant less home court advantage for the team starting in the first two home games, as the format now sees them miss out. Game 5 at home, which is a pivotal game in a series that goes all seven games.