NBA legend Bill Russell, an 11-time NBA champion with the Boston Celtics and the first Black head coach in the league, passed away Sunday, July 31, according to a family statement from his verified Twitter account. He was 88.

Russell's 11 championships with the Celtics included eight straight from 1959 to 1966. He was a five-time NBA MVP and a 12-time All-Star.

In 1966 Boston hired Russell to be the team's head coach, making him the first Black head coach in the NBA. He would serve as player-coach until the end of his career in 1969, winning two titles during his tenure.

Off the court, Russell was an activist committed to social justice and civil rights. In 1963 he marched alongside Martin Luther King Jr. when he gave his "I Have a Dream" and also supported iconic boxer Muhammad Ali in his opposition to being drafted into military service. Russell was the recipient of the Presidential Medal of Freedom in 2011.

In a statement issued by the Celtics, the team lauded Russell and his contributions to both the team and the sport as a whole.

"To be the greatest champion in your sport, to revolutionize the way the game is played, and to be a societal leader all at once seems unthinkable, but that is who Bill Russell was."

William Felton Russell was born on February 12, 1934 in Monroe, Louisiana. While attending college at the University of San Francisco, he led the university's basketball team in <a href="index.php?page=&url=https%3A%2F%2Fwww.cnn.com%2F2013%2F09%2F06%2Fus%2Fncaa-mens-basketball-tournament-fast-facts%2Findex.html" target="_blank">back-to-back NCAA championships</a> in 1955 and 1956.
William Felton Russell was born on February 12, 1934 in Monroe, Louisiana. While attending college at the University of San Francisco, he led the university's basketball team in back-to-back NCAA championships in 1955 and 1956.
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Russell poses in San Francisco in 1955. The 6-foot-9 center was known for his defense and skill in blocking shots.
Russell poses in San Francisco in 1955. The 6-foot-9 center was known for his defense and skill in blocking shots.
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From left, Russell shows his parents Katie and Charles Russell a telegram informing him he made the first string All-American team in Oakland, California, in February 1955.
From left, Russell shows his parents Katie and Charles Russell a telegram informing him he made the first string All-American team in Oakland, California, in February 1955.
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Russell is lifted up by fans after the USF Dons won the NCAA title in Kansas City, Missouri, in 1955. <br />
Russell is lifted up by fans after the USF Dons won the NCAA title in Kansas City, Missouri, in 1955.
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Russell and Rose Swisher wave to the crowd during a parade celebrating San Francisco's NCAA championship in San Francisco, California, in March 1955.
Russell and Rose Swisher wave to the crowd during a parade celebrating San Francisco's NCAA championship in San Francisco, California, in March 1955.
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Russell competes in the high jump for University of San Francisco during a track meet in April 1956. In the same month, Russell would be selected second overall in the NBA draft by the St. Louis Hawks, before being traded to the Boston Celtics.
Russell competes in the high jump for University of San Francisco during a track meet in April 1956. In the same month, Russell would be selected second overall in the NBA draft by the St. Louis Hawks, before being traded to the Boston Celtics.
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Russell and Swisher were married in Oakland, California, in 1956. The couple got hitched after Russell won the gold medal at the Melbourne Olympics.
Russell and Swisher were married in Oakland, California, in 1956. The couple got hitched after Russell won the gold medal at the Melbourne Olympics.
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Russell shoots hoops in February 1956.
Russell shoots hoops in February 1956.
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Russell signs autographs for young fans at San Francisco International Airport in March 1956.
Russell signs autographs for young fans at San Francisco International Airport in March 1956.
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Joined by co-owners Lou Pieri and Walter Brown, Russel signs a contract to join the Boston Celtics in December 1956. Russell was selected second overall in the 1956 NBA draft by the St. Louis Hawks and was later traded to Boston.
Joined by co-owners Lou Pieri and Walter Brown, Russel signs a contract to join the Boston Celtics in December 1956. Russell was selected second overall in the 1956 NBA draft by the St. Louis Hawks and was later traded to Boston.
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Russell takes a shot during a game against New York in 1957. Russell played his entire career as a center for Boston.
Russell takes a shot during a game against New York in 1957. Russell played his entire career as a center for Boston.
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Russell with his sons William Jr. "Buddha" and Jacob in April 1961.
Russell with his sons William Jr. "Buddha" and Jacob in April 1961.
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Russell relaxes in a whirlpool bath following a Celtics practice in San Francisco, California, in December 1963.
Russell relaxes in a whirlpool bath following a Celtics practice in San Francisco, California, in December 1963.
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From left, fans carry then-Celtics forward Tommy Heinsohn, coach Red Auerbach and Russell around the court after Boston won their sixth consecutive NBA title in 1964.
From left, fans carry then-Celtics forward Tommy Heinsohn, coach Red Auerbach and Russell around the court after Boston won their sixth consecutive NBA title in 1964.
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Russell, left, shoots over Cincinnati's Wayne Embry during a playoff game in Cincinnati, Ohio, in 1966.
Russell, left, shoots over Cincinnati's Wayne Embry during a playoff game in Cincinnati, Ohio, in 1966.
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Russell celebrates with Auerbach in the locker room after defeating Los Angeles to win the 1966 NBA title. It was the team's eighth consecutive championship and Russell's ninth overall. He would go on to win two more in 1968 and 1969.
Russell celebrates with Auerbach in the locker room after defeating Los Angeles to win the 1966 NBA title. It was the team's eighth consecutive championship and Russell's ninth overall. He would go on to win two more in 1968 and 1969.
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Russell, center left, and Auerbach look over an autographed ball after Russell was named Boston's head coach in 1966, making him the first Black head coach in NBA history.
Russell, center left, and Auerbach look over an autographed ball after Russell was named Boston's head coach in 1966, making him the first Black head coach in NBA history.
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Russell speaks about segregation during the Freedom Graduation at Patrick T. Campbell Jr. High School in Boston, Massachusetts, in June 1966. Russell was an outspoken supporter of civil rights.
Russell speaks about segregation during the Freedom Graduation at Patrick T. Campbell Jr. High School in Boston, Massachusetts, in June 1966. Russell was an outspoken supporter of civil rights.
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Russell, left, speaks with boxer and fellow civil rights trailblazer Muhammad Ali, in Cleveland, Ohio, in 1967. The two were joined by other Black athletes at a news conference in support of Ali's refusal to fight in the Vietnam War.
Russell, left, speaks with boxer and fellow civil rights trailblazer Muhammad Ali, in Cleveland, Ohio, in 1967. The two were joined by other Black athletes at a news conference in support of Ali's refusal to fight in the Vietnam War.
Tony Tomsic/AP
Russell, right, posts up against Philadelphia center Wilt Chamberlain during a game in Boston in 1968.<br />
Russell, right, posts up against Philadelphia center Wilt Chamberlain during a game in Boston in 1968.
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Russell and Keith Jackson call an NBA game in Milwaukee, Wisconsin, in 1972. Russell briefly Served as a commentator for televised basketball games in between his coaching jobs.
Russell and Keith Jackson call an NBA game in Milwaukee, Wisconsin, in 1972. Russell briefly Served as a commentator for televised basketball games in between his coaching jobs.
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Russell, left, coaches the Sacramento Kings in 1988. After retiring as a player, Russell went on to coach several NBA teams including the Seattle SuperSonics from 1973-1977 and Sacramento from 1987-1988.
Russell, left, coaches the Sacramento Kings in 1988. After retiring as a player, Russell went on to coach several NBA teams including the Seattle SuperSonics from 1973-1977 and Sacramento from 1987-1988.
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Russell poses for a portrait with Michael Jordan and his NBA Most Valuable Player trophy in Chicago in 1998.
Russell poses for a portrait with Michael Jordan and his NBA Most Valuable Player trophy in Chicago in 1998.
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Russell shares a laugh with Kobe Bryant during NBA All-Star weekend in Las Vegas, Nevada, in 2007.
Russell shares a laugh with Kobe Bryant during NBA All-Star weekend in Las Vegas, Nevada, in 2007.
Mark J. Terrill/AP
Russell <a href="index.php?page=&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DlTTUavCTXKk" target="_blank" target="_blank">speaks with Boston's Kevin Garnett</a> in Waltham, Massachusetts, in 2008.
Russell speaks with Boston's Kevin Garnett in Waltham, Massachusetts, in 2008.
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Then-President Barack Obama awards Russell the Presidential Medal of Freedom during a ceremony at the White House in Washington, DC, in February 2011.
Then-President Barack Obama awards Russell the Presidential Medal of Freedom during a ceremony at the White House in Washington, DC, in February 2011.
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Russell looks on as then-NBA Commissioner David Stern presents Miami forward LeBron James with the Bill Russell NBA Finals Most Valuable Player Award in June 2012. In 2009, the NBA renamed the Finals MVP Trophy to include Russell's name.
Russell looks on as then-NBA Commissioner David Stern presents Miami forward LeBron James with the Bill Russell NBA Finals Most Valuable Player Award in June 2012. In 2009, the NBA renamed the Finals MVP Trophy to include Russell's name.
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Russell is interviewed by Dr. Harry Edwards during the Civil Rights Summit in Austin, Texas, in 2014.
Russell is interviewed by Dr. Harry Edwards during the Civil Rights Summit in Austin, Texas, in 2014.
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Russell smiles as he is introduced before the NBA All-Star game in New Orleans, Louisiana, in 2017.
Russell smiles as he is introduced before the NBA All-Star game in New Orleans, Louisiana, in 2017.
Gerald Herbert/AP
Russell poses for a photo with his fourth wife, Jeannine, at an awards gala in Uncasville, Connecticut, a day before the 2021 Naismith Memorial Basketball Hall of Fame enshrinement ceremony. Russell, who was inducted into the Hall of Fame as a player in 1975, was inducted as coach in September 2021.
Russell poses for a photo with his fourth wife, Jeannine, at an awards gala in Uncasville, Connecticut, a day before the 2021 Naismith Memorial Basketball Hall of Fame enshrinement ceremony. Russell, who was inducted into the Hall of Fame as a player in 1975, was inducted as coach in September 2021.
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