During the perilous years of 1940-1941, a small band of Americans joined the Royal Air Force to help England resist Nazi Germany. They did so while the United States remained a neutral power and overcame significant obstacles to accomplish their objective. Over time, the RAF formed three fighter units, known collectively as the Eagle Squadrons, around these volunteer pilots. These Americans flew alongside their British comrades in fighter and bomber escort missions until 1942, when they transferred into the United States Army Air Forces. The Eagle Squadron pilots made noteworthy contributions to the RAF, assisting them in their transition from fighting a defensive war to waging an offensive campaign against the German Luftwaffe and helping pave the way to an eventual Allied victory.