A French fleet of 24 ships under Comte de Grasse defeat British forces under Admiral Thomas Graves and Samuel Hood at the Battle of the Chesapeake [Battle of the Virginia Capes] and trap General Lord Charles Cornwallis at Yorktown, 5 September 1781. This crucial battle of the American Revolution proved decisive in the Siege of Yorktown, effectively securing independence for the Thirteen Colonies.
6 September 1522: Ferdinand Magellan's Spanish expedition, now led by Juan Sebastián Elcano, returns to Seville without their captain after a three-year epic voyage, becoming the first to circumnavigate the globe. Pictured above is Magellan's ship Victoria, the only ship in the fleet to complete the circumnavigation. Detail from a map by Abraham Ortelius, 1590.