Frederick Albert Cook (June 10, 1865 – August 5, 1940) was an American explorer, physician, and ethnographer who is most known for allegedly being the first to reach the North Pole on April 21, 1908. A competing claim was made a year later by Robert Peary, though both men's accounts have since been fiercely disputed; in December 1909, after reviewing Cook's limited records, a commission of the University of Copenhagen ruled his claim unproven. Nonetheless, in 1911, Cook published a memoir of the expedition in which he maintained the veracity of his assertions. In addition, he also claimed to have been the first person to reach the summit of Denali (then known as Mount McKinley), the highest mountain in North America, a claim which has since been similarly discredited. Though he may not have achieved either Denali or the North Pole, his was the first and only expedition where a United States national discovered an Arctic island, Meighen Island.