[28] On May 9, the army engaged Confederate troops at Cloyd's Mountain, where the men charged the enemy entrenchments and drove the rebels from the field.[28] McKinley later said the combat there was "as desperate as any witnessed during the war".[28] Following the rout, the Union forces destroyed Confederate supplies and skirmished with the enemy again successfully.[28]
McKinley and his regiment moved to the Shenandoah Valley as the armies broke from winter quarters to resume hostilities. Crook's corps was attached to Major General David Hunter's Army of the Shenandoah and soon back in contact with Confederate forces, capturing Lexington, Virginia, on June 11.[29] They continued south toward Lynchburg, tearing up railroad track as they advanced.[29] Hunter believed the troops at Lynchburg were too powerful, however, and the brigade returned to West Virginia.[29] Before the army could make another attempt, Confederate General Jubal Early's raid into Maryland forced their recall to the north.[30]
Early's army surprised them at Kernstown on July 24, where McKinley came under heavy fire and the army was defeated.