A rear admiral in the uniformed services of the United States is either of two different ranks of commissioned officers: one-star flag officers and two-star flag officers. By contrast, in most other countries, the term "rear admiral" refers only to an officer of two-star rank. Rear admiral (lower half) Rear admiral (lower half) (abbreviated as RDML), is a one-star flag officer, with the pay grade of O-7 in the United States Navy, the United States Coast Guard, the United States Public Health Service Commissioned Corps, and the National Oceanic and Atmospheric Administration Commissioned Officer Corps. Rear admiral (lower half) ranks above captain and below rear admiral. Rear admiral (lower half) is equivalent to the rank of brigadier general in the United States Army, Air Force, Marine Corps, and Space Force and equivalent to the rank of commodore in most other navies. In the United States uniformed services, rear admiral (lower half) replaced the rank of commodore in 1985. Rear admiral Rear admiral (abbreviated as RADM), also sometimes referred to informally as "rear admiral (upper half)", is a two-star flag officer, with the pay grade of O-8 in the United States Navy, the United States Coast Guard, the United States Public Health Service Commissioned Corps, the National Oceanic and Atmospheric Administration Commissioned Officer Corps and the United States Maritime Service. Rear admiral ranks above rear admiral (lower half) and below vice admiral. Rear admiral is equivalent to the rank of major general in the U.S. Army, Air Force, Marine Corps, and Space Force. It is the highest permanent rank during peacetime in the uniformed services. All higher ranks are temporary ranks and linked to their specific commands or office and expire with the expiration of their term of command or office. History Before the American Civil War, the U.S. Navy had resisted creating the rank of admiral. Instead, they preferred the term "flag officer", in order to distinguish the rank from the traditions of the European navies. During the American Civil War, the U.S. Congress honored David Farragut's successful assault on the city of New Orleans by creating the rank of rear admiral on July 16, 1862. During World War II, the U.S. Navy and the U.S. Coast Guard both had a temporary one-star rank of commodore that was used in limited circumstances. By the end of the war, all incumbents had been advanced to the rank of two-star rear admiral