McCauley was born in Philadelphia, Pennsylvania, in the decade after the American Revolution and educated in the city's schools.

He served on the Constellation in 1813, and took part in the gunboat attack on the British naval frigate Narcissus in Hampton Roads, and in the defense of Craney Island.

For his success in this he was publicly complimented on his return in June by President Franklin Pierce at a dinner at the White House.

[1] Upon the outbreak of the American Civil War in 1861 he destroyed a large number of ships and property there, to prevent its falling into the hands of the Confederate States of America.

Nearly 2,000 cannon and several of the scuttled warships, including the USS Merrimack, were captured and returned to service by the Confederates.