Greenland is an autonomous country within the Danish Realm, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe (specifically Norway and Denmark, the colonial powers, as well as the nearby island of Iceland) for more than a millennium. In 2008, the people of Greenland passed a referendum supporting greater autonomy; 75% of votes cast were in favour. Greenland is the world's largest island, over three-quarters of which is covered by the only permanent ice sheet outside of Antarctica. With a population of about 56,480 (2013), it is the least densely populated country in the world.