Sir Martin Frobisher (; c. 1535 – 22 November 1594) was an English seaman and privateer who made three voyages to the New World looking for the North-west Passage. He probably sighted Resolution Island near Labrador in north-eastern Canada, before entering Frobisher Bay and landing on present-day Baffin Island.

On his second voyage, Frobisher found what he thought was gold ore and carried 200 tons of it home on three ships, where initial assaying determined it to be worth a profit of £5.20 per ton. Encouraged, Frobisher returned to Canada with an even larger fleet and dug several mines around Frobisher Bay. He carried 1,350 tons of the ore back to England, where, after years of smelting, it was realized that the ore was a worthless rock called hornblende. As an English privateer, he plundered riches from French ships. He was later knighted for his service in repelling the Spanish Armada in 1588.