It was formed in 1950 from the facilities of the United States established during World War II in eastern Canada, Newfoundland and Greenland.

The NBC was formed to command bases in Newfoundland which came under United States control as a result of the 1940 Destroyers for Bases Agreement; the 1941 US-Danish Agreement on Greenland, and the development by Air Transport Command of airfields in the Canadian Northwest Territories and Greenland to support aircraft ferry routes to Great Britain.

In exchange for the destroyers, the U. S. got ninety-nine-year leases for bases in Dominion of Newfoundland, Bermuda, British Guiana, Antigua, Trinidad, St. Lucia, Jamaica and the Bahamas.

The first USAAF presence in Newfoundland was in May 1941 when six B-18 Bolos from the First Air Force 21st Reconnaissance Squadron arrived at RCAF Station Gander.

With United States bases were under construction in Newfoundland, a number of possible sites for airfields in Greenland were made in late 1940.

Neither the United States, nor Canada or the UK desired any Wehrmacht facilities or armed forces in Greenland to obtain weather data.

During the summer of 1940 Nazi Germany had organized in Norway a number of expeditions for the purpose of establishing radio and weather stations in northeastern Greenland, in the neighborhood of Scoresby Sound.

A mixed British-Norwegian landing party seized a supply of aviation gasoline, dismantled several radio stations, and took into custody a number of heavily armed Danish "hunters" found on the coast.

In addition to seizing German ships and weather equipment on Greenland, the British and Canadians were planning on building air bases on the island to conduct antisubmarine warfare in the North Atlantic.

The Department of State reached an agreement on 9 April 1941 with Danish Foreign Minister, Henrik de Kauffmann, acting on behalf of His Majesty the King of Denmark in his capacity as sovereign of Greenland.

The agreement recognized that as a result of the European war there was danger that Greenland may be converted into a point of aggression against nations of the American Continent by Nazi Germany.

As soon as the agreement with the Danish Government was concluded, President Roosevelt authorized the War Department to go ahead with the preparations for building airfields and other facilities in Greenland.

Greenland Base Command (GBC) was established on 1 September 1941 with headquarters at Bluie West I to take charge of the U.S. forces and facilities being planned.

[9] By the end of September 1941, when the contractor's people arrived, the troops at Bluie West I had erected 85 buildings, about two-thirds of the total needed for the initial force, and had begun to install the necessary utilities.

By the time the civilian construction force arrived they had finished grading one of the two runways and had a metal landing mat partly laid.

Bluie West I was thus one of the earliest U.S. Army airfields, if not the first, to make actual use of Pierced Steel Planking (PSP) in runway construction, an important engineering development and one that afterwards contributed greatly to the winning of the war, particularly in the Pacific.

A third field was placed on the east coast almost directly across from BW-1 at Angmagssalik In addition, the United States obtained rights to build bases in Greenland.

An air patrol of the east coast, even after the new bases were completed proved its worth by assisting in the capture of the trawler Buskoe on 12 September, as that vessel, a small German-controlled Norwegian ship, was attempting to establish a radio and weather station in the Mackenzie Bay area.

The original mission of these airfields and stations was to aid in moving military aircraft to Great Britain as part of the Lend-Lease Act prior to American entry into World War II.

United States forces had taken over the defense of Iceland in July 1941, where they improved airstrips previously occupied by the RAF and began in the spring of 1942 to build two new air bases (Meeks and Patterson) near Keflavik.

At that time it was hoped that some of the disadvantages of the existing route might be overcome by developing a more northerly airway extending from Great Falls, Montana, across Canada to Hudson Bay and thence by way of Baffin Island to Bluie West Eight in Greenland.

In Canada, airfields were established at The Pas and Churchill in Manitoba; Southampton Island and a site code-named Crystal II in the Northwest Territories.

The Strategic Air Command East Reconnaissance Group (Project Nanook) flew B-17 mapping and photography missions from Thule's primitive facilities.

The War Department decided that there was no longer a requirement for active defense of the areas of the North Atlantic bases.

All United States Army and USAAF forces in Labrador and Northeast Canada were placed under the Newfoundland Base Command.

ATC was inactivated and control of NBC was reassigned to the new Military Air Transport Service (MATS) on 1 June 1948.

Overall responsibility for air defense was vested in ConAC, and plans were made for a chain of Ground Control Intercept radar stations in Greenland and northeast Canada to detect any long-range Soviet aircraft approaching, with squadrons of interceptor aircraft to defend the airspace of North America.

The shortest route from the US to the Soviet Union's most important industrial areas was over the North Pole, and Thule is at the precise midpoint between Moscow and New York.

Strategic Air Command bombers flying over the Arctic presented less risk of early warning than using bases in England.

Finally, ADC succeeded NEAC in its responsibilities for supporting and operating the Distant Early Warning Line radar stations in Canada and Greenland.