What is the highest permanent peacetime rank in the U.S. Army?

The higher ranks (lieutenant general and four-star general) are temporary ranks linked to specific positions, although virtually all officers who have been promoted to those ranks are approved to retire at their highest earned rank.

The rank of major general is a two-star general-officer and ranks above brigadier general and below lieutenant general. A major general typically commands division-sized units of around 10,000 to 15,000 soldiers. It is equivalent to the two-star rank of rear admiral in the U.S. Navy and U.S. Coast Guard.

Prior to the American Civil War, major general was the highest rank that could be attained by an officer. However, Winfield Scott had been given the brevet rank of lieutenant general in 1855, when he served as Commanding General of the U.S. Army. When George Washington died he was officially listed as holding the rank of lieutenant general, rather than full general, and it was regarded as improper for an officer to hold a rank equal to or superior to Washington's. To rectify the issue, Washington was promoted posthumously to General of the Armies in 1976.

Ulysses S. Grant was appointed lieutenant general when he took command of all Union forces in 1864. The Union army commanders following Scott (McClellan and Halleck) were major generals.