Pierre Morpain (c. 1686 - 20 August 1749) was a French ship's captain, privateer, and naval officer. Active in the waters of the West Indies, Morpain is best known for a highly successful privateering career along the coast of Acadia (and later Nova Scotia) during Queen Anne's War and King George's War. He notably made a providential arrival, with supply-laden prizes in tow, at the Acadian capital, Port Royal, not long after the first 1707 siege. In his later years he participated as a military commander in the defence of Fortress Louisbourg during the 1745 siege.
Pierre Morpain was born in Blaye, a community on the Gironde in southwestern France, in roughly 1686. His father, Jacques Morpain, was a local businessman. Both parents died when he was young, and by 1703 he was serving at sea. In 1706 he was given command of the Intrépide, based in the West Indies at Cap-Français (present-day Cap-Haïtien), with instructions to interfere with British shipping. In 1707 he cruised as far north as New England, where he captured two prizes: a ship full of provisions, and a slave ship. Since France and England were then at war, he made for the nearest safe port, which was Port Royal, the capital of Acadia. Unknown to Morpain, an English colonial force had recently abandoned a siege there, and the town was in desperate need of supplies. Morpain generously offered his captured stores to the town, winning the gratitude of Acadia's Governor Daniel d'Auger de Subercase. Fearing a renewed attack, Subercase asked Morpain to stay; the English returned in late August, and Morpain and his ship's crew assisted the Acadians in driving the besiegers off.