During the American Civil War, the Company was mustered into Federal service as Company F of the 1st Rhode Island Infantry (a.k.a. 1st Rhode Island Detached Militia) in April 1861 under the command of Captain (later Brevet Brigadier General) George W. Tew. It fought at the Battle of Bull Run in July and was mustered out of Federal service in August. Individual members of Company F volunteered for service with other regiments after they were mustered out of service in August 1861.