"Eric has been tremendous to the St. Louis Blues organization and the St. Louis community," said Doug Armstrong, the Blues vice president and general manager. "We wish him nothing but the best."
Brewer, 31, had been the Blues captain since the midway point of the 2008 season. He spent almost six seasons in St. Louis, recording 30 goals and 95 points in 332 games.
The Blues obtained defensive prospect Brock Beukeboom, son of former NHL defenseman Jeff Beukeboom.