Joseph Nelson Garland Whistler (October 19, 1822 – April 20, 1899) was a career United States Army officer. He served in the Mexican–American War and received a brevet appointment for distinguished service in the Battle of Contreras and the Battle of Churubusco. At the beginning of the American Civil War, Whistler was among the U.S. Regular Army officers taken prisoner by Confederates in Texas in April 1861 and paroled but was not exchanged until August 15, 1862. In 1863, he became colonel of the 2nd New York Heavy Artillery Regiment. He received a promotion and four brevet appointments in the regular army for his service during the Overland Campaign, specifically the Battle of North Anna, and the Siege of Petersburg, specifically the Second Battle of Petersburg. He was nominated on January 13, 1866 and confirmed on March 12, 1866 for appointment to the grade of brevet brigadier general of volunteers, to rank from March 13, 1866. He retired in on October 19, 1886 as colonel of the 15th U.S. Infantry Regiment.