Master commandant

Master commandant was a rank within the early United States Navy. The rank of master commandant was slightly higher than lieutenant, and a master commandant would often command warships too small to justify the command of a full captain. In the United States Navy, the rank was shortened to "commander" in 1838.

The early U.S. Navy had three "grades" of officer who were typically placed in charge of warships: captain; master commandant; and lieutenant, commanding (which was not a distinct rank, but a title given to an ordinary lieutenant). That structure remains largely in place in the modern American Navy, with the distinct ranks of captain, commander, and lieutenant commander.

Master commandant was roughly equivalent to the Royal Navy rank of master and commander, which itself was shortened to "commander" in 1794. When he was in command of a ship, such as a sloop or brig, a master commandant would be addressed as "Captain" by the sailors on board.

American naval hero Stephen Decatur notably never held the rank of master commandant. After leading a daring raid to destroy the captured U.S. frigate Philadelphia in Tripoli Harbor in 1804, Decatur returned to America as national hero and was given a direct promotion from lieutenant to captain.

Also in 1804, Master Commandant Richard Somers led a dozen volunteer sailors on the USS Intrepid—loaded with explosives—toward the pirate fleet in the harbor of Tripoli, Libya.

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