Field officer rank category (OF-3 to OF-5) of the Russian Imperial Army and Navy until 1917. The British Army (in which these officers are called officers of field rank), and some others in the Commonwealth (including the Australian Army and New Zealand Army), also include the brigadier in this category: the equivalent in other armies is a general officer (the brigadier general). Today, a field officer in the United States (here called field grade) Army, Marine Corps, and Air Force is typically a major, lieutenant colonel, or a colonel: Field officer A field officer, field-grade officer, or senior officer is an army,
Lieutenant colonel (United States) 1791, there was only one lieutenant colonel in the US Army (Josiah Harmar), who acted as the army's commanding officer. In the Continental Army aides to the Commander in Chief, viz., Lieutenant General George Washington, were lieutenant colonels. Additionally, certain officers serving under the Adjutant General, Inspector General, and Judge Advocate General, ranked as lieutenant colonels. During the 19th century, lieutenant colonel was often a terminal rank for many officers, since the rank of "full colonel" was considered extremely prestigious reserved only for the most successful officers. Upon the outbreak of the Civil War, the rank of lieutenant colonel became