Howe's contentious relationships with superior officers in the Army of the Potomac eventually led to his being deprived of division command.

Howe received the brevet rank of major in the regular army for his role at the Battle of Malvern Hill.

Howe's division led a reconnaissance in the vicinity of Fredericksburg on June 3, 1863, as the Union high command tried to determine whether the Army of Northern Virginia was moving out of its positions to undertake an offensive.

His division was the last to reach the battlefield and his two brigades were assigned to opposite ends of the Union line, leaving him effectively without a command.

[1] During the pursuit of Lee's retreating army, the 1st Vermont Brigade of Howe's division fought the Confederate rear guard near Funkstown, Maryland, on July 10, 1863.

Howe's bad relationship with his corps commander, Maj. Gen. John Sedgwick, including support of Maj. Gen. Joseph Hooker in the controversies that were spawned by the Union defeat at Chancellorsville, probably contributed to this removal.

He was in the field briefly at Harpers Ferry, opposing the raid on Washington by Confederate Lieutenant General Jubal Early.

Howe did not make any public comments on the conviction or hanging of Mary E. Surratt, but was not among the five officers who petitioned President Andrew Johnson to commute her sentence to life in prison.