Subban said he was not surprised by the trade because there had been so many rumors since he signed a $72 million, eight-year contract in the summer of 2014. His no-movement clause was set to kick in Friday, meaning this was the last window for the Canadiens to listen to offers on him.
"With a lot of the chatter that kind of happened over the little while, I'm a firm believer that, usually, where there's smoke there's fire,'' Subban said on a conference call. "Obviously, it's a little bit surreal, but it happened.''
Nashville general manager David Poile said the trade was first discussed at the draft last weekend in Buffalo. He said it was worth it to give up Weber for Subban.
"P.K. Subban is an elite offensive defenseman with tremendous skill and contagious energy that makes the Nashville Predators a better team now and into the future," Poile said in a statement. "Superstar defensemen of his caliber are a rare commodity, and we are thrilled to add him to the organization."
Subban, 27, won the Norris Trophy, given to the NHL's top defenseman, in 2013. He has scored more than 50 points in each of the past three seasons, including a career-best 60 points in the 2014-15 season. He had six goals and 45 assists last season before suffering an injury.
Subban has 63 goals and 215 assists in 434 career games, all with the Canadiens.
Weber, who turns 31 on Aug. 14, has scored more than 50 points in two of the past three seasons. A three-time Norris Trophy finalist, he was a team captain and had 20 goals and 31 assists last season.His 14 power-play goals last season led all NHL defensemen.
Weber had been with Nashville since the start of his NHL career in 2005. He signed a $110 million, 14-year offer sheet with the Philadelphia Flyers as a restricted free agent in 2012, but Nashville matched it to keep him.
"We completed today an important transaction which I am convinced will make the Canadiens a better team," general manager Marc Bergevin said in a statement. "It was also one of the most difficult decisions I had to make as general manager of the Montreal Canadiens. In Shea Weber, we get a top rated NHL defenseman with tremendous leadership, and a player who will improve our defensive group as well as our power play for many years to come. He is a complete rearguard with impressive size and a powerful shot.
"P.K. Subban is a special and very talented player. He provided the Canadiens organization with strong performances on the ice and generous commitment in the community. I wish him the best of luck with the Predators."
Subban has five more years left on his contract, paying him an average of $9 million per season.
Weber has 10 more years at a $7.857 million cap hit, although it was a 14-year deal signed in 2012 that was massively front-loaded, seeing his salary go from $12 million next season to $6 million in 2018-19, $3 million 2022-23 and then $1 million each of the final three years through 2025-26.
Both Weber and Subban were members of Team Canada's Olympic gold medal team in 2014.
Subban said he always felt wanted in the Montreal community after he was drafted in the second round in 2007. He stopped short of saying he felt unwanted by the Canadiens.
"I just feel good knowing that a team has moved someone to bring me in because they want me," Subban said while on vacation in Paris. "Just happy to be in a situation where I can excel and feel good coming to the rink every day about myself, about the team, about my position. More importantly, I just look forward to trying to win a Stanley Cup. That's your ultimate goal, and I feel that I got a whole lot closer to doing that today."
The Associated Press contributed to this report.