Henry H. Arnold in the context of "General officers in the United States"

General of the Army (abbreviated as GA) is a five-star general officer rank in the United States Army. It is generally equivalent to the rank of field marshal in other countries. In the United States, a General of the Army ranks above generals and is equivalent to a fleet admiral and a general of the Air Force. The General of the Army insignia consisted of five 3⁄8-inch (9.5 mm) stars in a pentagonal pattern, with touching points. The insignia was paired with the gold and enameled United States coat of arms on service coat shoulder loops. The silver colored five-star chain has major insignia alone would be worn for use as a collar insignia of grade and on the garrison cap. Soft shoulder epaulets with five 7⁄16-inch (11 mm) stars in silver thread and gold-threaded United States coat of arms on green cloth were worn with shirts and sweaters.

The rank of "General of the Army" (the highest rank in the army) has had two incarnations. The first was introduced in 1866, following the American Civil War. While it was nominally a four-star rank, structurally it had authority over the entire Army; it was reserved for the Commanding General of the United States Army, and was held by three different men in succession from 1866 to 1888: Ulysses S. Grant, William Tecumseh Sherman and Philip Sheridan. When it was created by Congress for Grant, Grant had already reached the highest rank historically used in the United States, the three star lieutenant general. The "General of the Army" rank was revived during World War II as the modern five-star rank. The rank does not imply command of the entire Army and may be awarded to more than one officer at a time. It has been held by five different men since 1944, four promoted to the rank in December 1944 (George C. Marshall, Douglas MacArthur, Dwight D. Eisenhower, Henry H. Arnold), and one promoted in September 1950 (Omar Bradley).

The military history of the United States during World War II covers the nation's role as one of the major Allies in their victory over the Axis powers. The United States is generally considered to have entered the conflict with the 7 December 1941 surprise attack on Pearl Harbor by Japan and exited it with the surrender of Japan on 2 September 1945. During the first two years of World War II, the U.S. maintained formal neutrality, which was officially announced in the Quarantine Speech delivered by President Franklin D. Roosevelt in 1937. While officially neutral, the U.S. supplied Britain, the Soviet Union, and China with war materiel through the Lend-Lease Act signed into law on 11 March 1941, and deployed the U.S. military to replace the British forces stationed in Iceland. Following the 4 September 1941 Greer incident involving a German submarine, Roosevelt publicly confirmed a "shoot on sight" order on 11 September, effectively declaring naval war on Germany and Italy in the Battle of the Atlantic. In the Pacific Theater, there was unofficial early US combat activity such as the Flying Tigers.

During the war, some 16,112,566 Americans served in the United States Armed Forces, with 407,316 killed and 671,278 wounded. According to the US Department of Defense, of the 407,316 dead, about 250,000 were killed in the European theater, the remaining 160,000 died in the Pacific War. There were also 130,201 American prisoners of war, of whom 116,129 returned home after the war. Key civilian advisors to President Roosevelt included Secretary of War Henry L. Stimson, who mobilized the nation's industries and induction centers to supply the U.S. Army, commanded by General George C. Marshall and the Army Air Forces under General Henry H. Arnold. The U.S. Navy, led by Secretary of the Navy Frank Knox and Admiral Ernest J. King, proved more autonomous. Overall priorities were set by Roosevelt and the Joint Chiefs of Staff, chaired by William D. Leahy. The defeat of the Nazis was the U.S.'s official highest priority per its agreement with Britain; however, in practice, the US devoted more resources to the Pacific than Europe and Africa until 1944.

The Combined Chiefs of Staff (CCS) was the supreme military staff for the United States and Britain during World War II. It set all the major policy decisions for the two nations, subject to the approvals of British Prime Minister Winston Churchill and U.S. President Franklin D. Roosevelt.

General of the Air Force (GAF) is a five-star general officer rank and is the highest possible rank in the United States Air Force. General of the Air Force ranks immediately above a general and is equivalent to General of the Army in the United States Army and fleet admiral in the United States Navy. The rank has only been held by one man, General Henry H. Arnold, who had served as head of the United States Army Air Forces during World War II. As at the time of his promotion, the Air Force was a component of the Army instead of its own branch, and as a consequence, the rank has not been first awarded to someone who is serving in the Air Force. Arnold retained the rank when the separate branch was created, and he was redesignated General of the Air Force in 1949.