45th Infantry Battalion was organized by detachments between April and December 1863. Its six companies were composed of men from the 1st Regiment Cavalry Virginia State Line, which had disbanded. The unit served in the Department of Western Virginia, lost 4 killed and 11 wounded at Cloyd's Mountain, then was involved in various conflicts in the Shenandoah Valley. It disbanded during April 1865. Lieutenant Colonel Henry M. Beckley and Major Blake L. Woodson were in command.