John Clarke was an English captain who served in the garrison of Fort Algernon, Virginia during the 1610s. In 1611, he was sent out to the Spanish ship La Nuestra Senora del Rosario to guide the ship to safer anchorage, but the crew - which had disembarked the spies Diego de Molina, Francis Lembry, and Marco Antonio de Perez at Point Comfort - panicked, believing that Clarke would lure the ship into range of Fort Algernon's guns. The Spanish instead seized Clarke and returned to Havana, where Clarke was held until 1616, when he was exchanged for Molina in a prisoner exchange.