Ambrose Everts Burnside (May 23, 1824 – September 13, 1881) was an American army officer and politician who became a senior Union general in the American Civil War and a three-time governor of Rhode Island, as well as being an inventor and industrialist.
He achieved some of the earliest victories in the Eastern theater of the Civil War, but was then promoted above his abilities, and is mainly remembered for two disastrous defeats, at Fredericksburg (December 1862) and the Battle of the Crater (July 1864, during the Siege of Petersburg). Although an inquiry cleared him of blame in the latter case, he never regained credibility as an army commander.
Burnside was a modest and unassuming individual, mindful of his limitations, who had been propelled to high command against his will. He could be described as a genuinely unlucky man, both in battle and in commerce (due to various circumstances, most of them beyond his control, he was unable to profit from the successful cavalry firearm that had been his own invention). His style of thick facial hair became known as "sideburns", deriving from the two syllables of his surname.