“From the Halls of Montezuma, To the shores of Tripoli”  — so go the first two lines of the U.S. Marine battle hymn, referring the the earliest battles fought by a United States — the Halls of Montezuma referring to Mexico, and the Shores of Tripoli to the war against the Barbary, the first war fought outside its border by a unified United States. who were a constant menace to American ships, and during the wars with England, Spain and Mexico it was easier to pay tribute than to fight the pirates. That calculus changed with the United States established, and with the cry “millions for defense, not one cent for tribute!” war was declared on Tripoli.

On this day, April 27, a Marine raid on the fortress stronghold of Derne captured the city. The defenders put up only sparse defense, and fled almost immediately after the initial bombardment. When the flag was raised over the city, it was the fist time an American flag flew on the other side of the Atlantic.

The treaty with Tripoli concluded, the U.S. retreated briefly to fight the British in the War of 1812. In 1815 they returned in force, and with a bit of gunboat diplomacy brought the rulers of the other Barbary pirate states — Tunis, Morocco, Algiers, — under heel.