James Cook

James Cook joined the merchant navy as a teenager, then enlisted in the Royal Navy in 1755, seeing combat in the Seven Years' War and earning notice for his survey work along the St. Lawrence River and Newfoundland's coast. His mapping skill and astronomical observations caught the eye of the Admiralty and Royal Society at the exact moment Britain was pushing into the Pacific, landing him command of HMS Endeavour in 1768 for the first of three voyages that would carry him tens of thousands of miles across uncharted ocean. Over the next decade he mapped coastlines and islands - Easter Island, Alaska, South Georgia - in unprecedented detail, made contact with indigenous populations, claimed territories for Britain, and developed methods to prevent scurvy that won him the Royal Society's Copley Gold Medal. Patient and competent but occasionally hot-tempered, he returned to Hawaii in 1779; a dispute with Native Hawaiians turned violent and he was killed on 14 February, leaving behind charts and records that shaped exploration for the next century.