All black military pilots who trained in the United States trained at Moton Field, the Tuskegee Army Air Field, and were educated at Tuskegee University, located near Tuskegee, Alabama. The group included five Haitians from the Haitian Air Force, and one pilot from Trinidad.^[2]. It also included a Hispanic or Latino airman born in the Dominican Republic^[3].

Although the 477th Bombardment Group trained with North American B-25 Mitchell bombers, they never served in combat. The 99th Pursuit Squadron (later, 99th Fighter Squadron) was the first black flying squadron, and the first to deploy overseas (to North Africa in April 1943, and later to Sicily and Italy). The 332nd Fighter Group, which originally included the 100th, 301st, and 302nd Fighter Squadrons, was the first black flying group. It deployed to Italy in early 1944. In June 1944, the 332nd Fighter Group began flying heavy bomber escort missions, and in July 1944, with the addition of the 99th Fighter Squadron, it had four fighter squadrons.

The 99th Fighter Squadron was initially equipped with Curtiss P-40 Warhawk fighter-bomber aircraft. The 332nd Fighter Group and its 100th, 301st and 302nd Fighter Squadrons were equipped for initial combat missions with Bell P-39 Airacobras (March 1944), later with Republic P-47 Thunderbolts (June–July 1944), and finally with the aircraft with which they became most commonly associated, the North American P-51 Mustang (July 1944). When the pilots of the 332nd Fighter Group painted the tails of their P-47s red, the nickname "Red Tails" was coined. The red markings that distinguished the Tuskegee Airmen included red bands on the noses of P-51s as well as a red rudder; the P-51B and D Mustangs flew with similar color schemes, with red propeller spinners, yellow wing bands and all-red tail surfaces.

The Tuskegee Airmen were the first African-American military aviators in the United States Armed Forces. During World War II, black Americans in many U.S. states were still subject to the Jim Crow laws^{[N 1]} and the American military was racially segregated, as was much of the federal government. The Tuskegee Airmen were subjected to discrimination, both within and outside the army.

The program was under the direct control of the White House, with Roosevelt paying close attention, assisted by Harry Hopkins, W. Averell Harriman, Edward Stettinius Jr.. Roosevelt often sent them on special missions to London and Moscow, where their control over Lend Lease gave them importance. The budget was hidden away in the overall military budget, and details were not released until after the war.

A total of $50.1 billion (equivalent to $681 billion presently) was involved, or 11% of the total war expenditures of the U.S.^[2] In all, $31.4 billion (equivalent to $427 billion today) went to Britain and its Empire, $11.3 billion (equivalent to $154 billion today) to the Soviet Union, $3.2 billion (equivalent to $43.5 billion today) to France, $1.6 billion (equivalent to $21.7 billion today) to China, and the remaining $2.6 billion to the other Allies. Reverse lend-lease policies comprised services such as rent on bases used by the U.S., and totaled $7.8 billion; of this, $6.8 billion came from the British and the Commonwealth, mostly Australia and India. The terms of the agreement provided that the materiel was to be used until returned or destroyed. In practice very little equipment was in usable shape for peacetime uses. Supplies that arrived after the termination date were sold to Britain at a large discount for £1.075 billion, using long-term loans from the United States. Canada was not part of Lend Lease. However it operated a similar program called Mutual Aid that sent a loan of $1 billion and $3.4 billion in supplies and services to Britain and other Allies.^[3][4]

This program effectively ended the United States' pretense of neutrality and was a decisive change from non-interventionist policy, which had dominated United States foreign relations since 1931. (See Neutrality Acts of 1930s.)