On January 27, 2017, in a ceremony during the All-Star Weekend in Los Angeles, Chelios became part of the second group of players to be named one of the '100 Greatest NHL Players' in history.
Chelios played for the Montreal Canadiens, Chicago Blackhawks, Detroit Red Wings, and briefly for the Atlanta Thrashers. When he was called up from the AHL's Chicago Wolves to play for the Thrashers during the 2009–10 NHL season, Chelios was the oldest active player in the NHL and the second oldest of all time, had played the most games of any active player in the NHL, was the last player from the 1981 NHL Entry Draft still active (or any draft from 1986 and earlier), and had the most career penalty minutes of any active player. Chelios currently holds the record for most games played in the NHL by a defenseman, is fifth overall with 1,651 games played, and is tied with Gordie Howe for most NHL seasons played with 26. On November 24, 2006, he appeared in the playoffs for an NHL record 24th time, having missed the playoffs only once (1997–98). Chelios is also the record-holder for most career postseason losses, with 117 (also the most in any professional sport in North America). However, he only lost one Game 7 in his entire career, a 3-2 OT loss in the 1985 Adams Division Finals against the Nordiques.
Chelios is of Greek heritage. His cousin, Nikos Tselios, also played professional hockey and is a former first round draft pick of the Carolina Hurricanes. Chelios was inducted into the Hockey Hall of Fame on November 8, 2013.
Chelios was born in Chicago, Illinois on January 25, 1962, and raised by his parents, Gus and Susan Chelios. They lived in Evergreen Park, Illinois. He attended Mount Carmel High School in Chicago until his family moved to Poway, California, where he attended Mira Mesa High School.
Unable to play high school hockey in southern California, Chelios wasn't recruited by any U.S. colleges. His only scholarship offer came from local San Diego-based United States International University, the only NCAA Division I hockey team west of the Rockies. But when Chelios arrived on campus as a freshman in 1979 he soon realized he was in the wrong environment, facing bigger players with considerably more junior hockey experience. He was eventually cut from the team and considered quitting hockey. Instead, he tried his luck in Canada, where he was twice cut by Junior B teams in Canada and hit a low point when he had to borrow money from strangers to get home to California one year. Chelios said, "I wasn't any bigger or any better than the other guys, so they weren't going to take a kid from the States when they could have a local guy."