The name was given by Charles Wilkes during the Wilkes Expedition of 1838-1842, in honor of John Clark, a midshipman who was killed during the Battle of Lake Erie of the War of 1812. The island, along with nearby Barnes Island, had been named "Islas de Aquays" in 1792, by the Spanish explorer Francisco de Eliza, in honor of Eliza's patron, the Viceroy of Mexico, Juan Vicente de Güemes Padilla Horcasitas y Aguayo, 2nd Count of Revillagigedo.