Signed as an unrestricted free agent, he was coming to Boston as its captain, a new era of Bruins hockey in his sights.
"That was the changing moment for the Boston Bruins," former teammate Torey Krug said. "He changed the culture. He changed the standards."
He changed the fortunes of the Bruins, stung eight months earlier by the trade of Joe Thornton to the San Jose Sharks, and ushered in a period when Boston would win the Stanley Cup once, in 2011 with a seven-game victory against the Vancouver Canucks, and go to the Cup Final two more times, in 2013 and 2019.
And now, with the decision by the Bruins not to re-sign him and the news Wednesday that the 43-year-old agreed to a one-year, $795,000 contract with the Washington Capitals, that era is over.
"He gave the Bruins the identity that they've been playing with for the last 14 years he was there," former defense partner Dennis Seidenberg said. "And he was part of that culture change that he brought with him when [former general manager Peter] Chiarelli signed him to that first contract with the Bruins and ever since I think they didn't look back."
It wasn't Chara alone, of course. Mark Recchi was there. Patrice Bergeron. The heart and soul were spread among a group of leaders that carried the Bruins forward. But the driving, propelling force always was Chara.
"He set the bar in so many different ways, as far as work ethic, leadership, commitment, communication, empathy, you name it," said Shawn Thornton, a forward who played with Chara in Boston for seven seasons from 2007-14. "You had to give it everything you had, just to keep up to the pace he was pushing in all those different areas."
He was the first on the ice and often the last off it.
He was the one who was the Bruins' pullup champion in fitness testing as recently as 2017, when he was 40 years old, besting players half his age.
He scored 481 points (148 goals, 333 assists) in 1,023 games over 14 seasons with Boston, part of a 22-season career in which he has so far scored 656 points (205 goals, 451 assists) in 1,553 games for the Bruins, Ottawa Senators and New York Islanders while being one of the best shutdown defensemen of all time.