Lovie Smith, who was Adam Archuleta's defensive coordinator in St. Louis, has been trying to acquire the safety since becoming the head coach in Chicago.
On Tuesday, the Bears completed a trade with the Redskins for the 29-year-old. Chicago gave up a 2007 draft choice, believed to be in the sixth round.
After five seasons in St. Louis, Archuleta struggled in his first season with the Redskins in 2006 and was scheduled to be a backup this season in Washington.
To complete this complicated deal, the Bears had to rework Archuleta's contract. He had a guaranteed $5 million option bonus due last week, but with hopes of getting a trade, Archuleta delayed the execution of that payout until Wednesday.
Faced with the deadline, everyone worked on getting a deal done. The Bears will pay Archuleta $8.1 million over the next three years. The Redskins rid themselves of his $25 million contract. A total of $5 million of Archuleta's new deal in Chicago is guaranteed.
The Bears were looking for a playmaker at the safety position. Smith created defenses involving Archuleta when they were in St. Louis. In Chicago, Archuleta will have more opportunities to make plays at the line of scrimmage.
The Redskins made another move in the defensive backfield on Tuesday, reaching agreement on a one-year deal with safety Omar Stoutmire. Stoutmire, who played for Washington in 2005, has also played for the Cowboys, Jets, Giants, and Saints in his 10-year NFL career.
Senior writer John Clayton covers the NFL for ESPN.com.