The Redskins announced the hiring Thursday.
Callahan, who went to the 2003 Super Bowl as head coach of the Oakland Raiders, held titles of offensive coordinator and offensive line coach while with Dallas. He served for a time as play-caller for the Cowboys, but those duties were taken away this season.
His resume includes working as offensive line coach of the New York Jets from 2008-11, and as head coach of Nebraska in college football from 2003-06.
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