Joseph Hooker (1814-1879) was a Major General in the United States Army during the American Civil War.

Hooker was popularly known as "Fighting Joe" Hooker, a nickname which he detested. He was a 1837 graduate of West Point and served in the Mexican War.

Hooker replaced Ambrose Burnside as commander of the Army of the Potomac after Burnside was defeated at the Battle of Fredericksburg.

Hooker commanded the Army of the Potomac during the Battle of Chancellorsville where his planned campaign toward the Confederate capital was stopped by Confederate General Robert E. Lee through a devastating attack on Hooker's exposed right flank by General Thomas J. Jackson. The Battle of Chancellorsville is often referred to as 'Lee's Masterpiece'. Hooker resigned in 1863 during the early part of the Gettysburg campaign and was replaced by General George Meade soon after this setback.

Hooker went on to gain a reputation as a solid commander when he was transferred with the 11th and 12th Corps of the Army of the Potomac westwards to reinforce The Army of the Cumberland around Chattanooga, Tennessee. Hooker was in command at the Battle of Lookout Mountain (also known as The Battle Above the Clouds) and succeeded in capturing the important mountain for the Union.

Hooker participated in the Atlanta campaign but asked to be relieved before capture of the city. He was transferred to the north where he remained for the rest of the war.

There is no basis for the popular legend that the slang term for prostitutes came from his last name due to a certain lack of military discipline at his headquarters. The term "hooker" was used in print as early as 1845, many years before Hooker was a public figure.

Hooker died in Garden City, New York, on 31 October 1879 and is buried in Cincinnati, Ohio.