Flying over 300 combat missions, the group earned two Distinguished Unit Citations (Regensburg, 17 August 1943; Berlin, 4/6/8 March 1944).

The group suffered tremendous losses in combat, with 177 aircraft missing in action (MIA), flying its last mission on 20 April 1945.

Following this, the 100th BG relocated to Wendover Field, Utah, on 30 November where it added additional personnel, aircraft, and crews, and began bombing, gunnery, and navigation training.

After additional training, the group's aircrews departed Kearney on 25 May 1943, flying the North Atlantic route to England and into the war in Europe.

On 27 May 1943, the ground personnel set sail aboard the RMS Queen Elizabeth bound for Podington, England, from New York.

At Podington the ground crews rendezvoused with the air echelon, and together moved to RAF Thorpe Abbotts, Norfolk, where they remained throughout World War II, operating as a strategic bombardment organization.

On 25 June 1943, the 100th BG flew its first Eighth Air Force combat mission, bombing the U-boat yards at Bremen – the beginning of the "Bloody Hundredth"'s legacy.

The group focused its bombing attacks against German airfields, industrial plants, and naval facilities in France, Germany, Poland, the Netherlands, Norway, Romania, and Ukraine.

In February 1944, the group participated in Operation Argument ("Big Week"), the Allied attempt to force a decisive battle with the Luftwaffe and gain air superiority over Western Europe before the invasion of France.

In October 1944, the 100th BG attacked enemy defenses in the Allied drive on the Siegfried Line, then bombed marshaling yards, German occupied villages, and communication targets in the Ardennes during the Battle of the Bulge from December 1944 to January 1945.

The following month the unit's aircrews dropped food to the people in the west of the Netherlands, and in June transported French Allied former prisoners of war from Austria to France.

From the time of its activation, the group trained and operated as a reserve B-29 Superfortress unit being attached to the 49th Bombardment Wing (Later Air Division).

The 100th Bomb Wing was assigned the new B-47E Stratojet swept-wing medium bombers in 1954, capable of flying at high subsonic speeds and primarily designed for penetrating the airspace of the Soviet Union.

In official parlance, the establishment "...performed global strategic bombardment training and air refueling missions."

In October 1965, the Air Force initiated Project Fast Fly to oversee the inactivation of the last five B-47 wings and supporting tanker squadrons.

On 11 July 1970, the force was moved from Bien Hoa to U-Tapao RTNAF (OL-RU) and then turned to (OL-UA in Nov. 1970) Thailand.

The U-2s were one of the last units to be pulled out of Thailand in March 1976, With the end of United States combat operations in Southeast Asia in mid-1973, the Air Force formally transferred nuclear air sampling operations to the 100th SRW, and the 349th SRS converted its U-2s to the U-2R configuration for atmospheric sampling missions, replacing the WB-57s which it inherited from the 4028th SRS.

Not until the Communist Chinese had actually exploded their sixteenth nuclear device on 17 June 1974, could Headquarters USAF announce that all negotiations were concluded.

At the same time, it directed Headquarters SAC to deploy the 349th SRS "OLYMPIC RACE" assets to Osan and begin collecting from that location on 18 June 1974.

These U-2s engaged in OLYMPIC FIRE missions over Cuba, which were coordinated with the Joint Air Reconnaissance Control Center at NAS Key West, Florida.

With the redesignation, the 100th and its 349th and 350th Air Refueling Squadrons were moved administratively to Beale, taking over the assets of the 17th Bombardment Wing which was inactivated.

Becoming the host wing at RAF Mildenhall, the 100th ARW took over the management of the European Tanker Task Force (ETTF).