<P> The Celtics have a notable rivalry with the Los Angeles Lakers, and have played the Lakers a record 12 times in the NBA Finals (including their most recent appearances in 2008 and 2010), of which the Celtics have won 9 . Four Celtics players (Bob Cousy, Bill Russell, Dave Cowens and Larry Bird) have won the NBA Most Valuable Player Award for an NBA record total of 10 MVP awards . Both the nickname "Celtics" and their mascot "Lucky the Leprechaun" are a nod to Boston's historically large Irish population . </P> <P> After winning sixteen championships throughout the 20th century, the Celtics rose again after struggling through the 1990s to win a championship in 2008 with the help of Kevin Garnett, Paul Pierce, and Ray Allen in what was known as the new "Big Three" era, following the original "Big Three" era that featured Larry Bird, Kevin McHale, and Robert Parish, which combined to win the 1981, 1984, and 1986 championships . </P> <P> Following the win in 2008, general manager Danny Ainge began a rebuilding process with the help of head coach Brad Stevens, who led the Celtics to a return to the playoffs from 2015 . During the following season, the Celtics clinched the top seed in the Eastern Conference, and eventually reached the Conference Finals prior to losing to the Cleveland Cavaliers in five games . </P> <P> The Boston Celtics were formed on June 5, 1943 by Boston Garden - Arena Corporation President Walter A. Brown as a team in the Basketball Association of America, and became part of the National Basketball Association after the absorption of the National Basketball League by the BAA in the fall of 1949 . In 1950, the Celtics signed Chuck Cooper, becoming the first NBA franchise to draft a black player . </P>

When was the last time the celtics went to the finals
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