Frederick Townsend (September 21, 1825 – September 12, 1897) was a Union officer in the American Civil War. He founded and was Colonel of the 3rd New York Infantry Regiment, and later served with the US Army's 18th and 9th Infantry regiments, where he was brevetted a brigadier general. Townsend served three terms as Adjutant General of New York from 1857–1861, and again in 1880.