The first person to reach the North Pole has long been a matter of controversy and debate between two American explorers, and their supporters, both of whom claimed to have been the first, and both of whom disputed the other's claim as a fraud, whether intentional or not. Robert Peary, travelling with Matt Henson (USA), indicated he had reached the North Pole on 6 April 1909, however Frederick Cook, claimed he had done so a year earlier, on 21 April 1908. Despite investigations into the claims (both at the time and since) neither can be unquestionably proven.
What is agreed, is that the first person to reach the North Pole - on foot (with dogs, but supported by airdrops) - was Sir Wally Herbert (UK), on 6 April 1969. On 4 May 1990, Børge Ousland and Erling Kagge reached the North Pole on skis without resupply, after a journey lasting 58 days, making them the first people to reach the North Pole unsupported. (A third companion, Geir Randby, was injured en route and had to abandon the expedition.)
The first person to walk, solo and unsupported to the North Pole was Børge Ousland (Norway) in 1994.
Other points: At the time, and after initial hesitation, the Royal Geographical Society supported Peary's claim. However, it now supports neither Peary's nor Cook's. The National Geographic Society (USA) sponsored Peary's expedition, and in 1989 concluded that Peary was within five miles of the Pole. But as sponsor, can their judgement be relied upon? In 2005, Tom Avery (UK) and Matty McNair (USA) effectively renacted Peary's 1909 journey, even beating Peary's 37-day trip. This does not necessarily prove Peary's claim as more reliable, as Avery and McNair were airlifted from the Pole, thus allowing them to travel with less supplies.
Comments below may relate to previous holders of this record.