On January 13, 1866, President Andrew Johnson nominated Devens for the award of the honorary grade of brevet major general, United States Volunteers, to rank from April 3, 1865, for services during the Richmond campaign, and the U.S. Senate confirmed the award on March 12, 1866. Devens remained in the army for a year as commander of the military district of Charleston, South Carolina, before mustering out and returning home. He later served as the fifth Commander-in-Chief of the Grand Army of the Republic from 1873–75 and was also a veteran companion of the Military Order of the Loyal Legion of the United States.