Greenland was first explored by Eric the Red, a Norwegian settler in Iceland and father of Leif Eriksson, toward the end of the 10th century, and Icelandic settlements were consequently accomplished there under his leadership. By the early 15th century, these settlements had vanished, and all contact with Greenland was lost. In the course of the search for the Northwest Passage, Greenland was sighted again. The English navigator John Davis visited the island in 1585, and his explorative work, together with that of the English explorers Henry Hudson and William Baffin, afforded knowledge of the west coast of Greenland.

Greenland is the source of many of the weather changes in the northern hemisphere, and knowledge of Greenland weather is of prime importance for the prediction of conditions in the North Atlantic Ocean and in western Europe. Weather and radio stations are of inestimable value for Atlantic air traffic. In 1944, during World War II, a German radio-weather station on the northeast coast was destroyed by the U.S. Coast Guard, and various German attempts to establish weather bases on Greenland were thwarted by Coast Guard vessels. In May 1947, Denmark requested that the United States end the 1941 agreement. Protracted negotiations culminated during April 1951, in a 20-year pact providing for Danish control of the chief U.S. naval station in Greenland and for the establishment of jointly operated defense areas. By the terms of other provisions, the armed forces of the members of the North Atlantic Treaty Organization were authorized to use all naval, air, and military bases on the island.