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Mechanist Sergeant-Major (British Army)

Navies Armies Air forces
Commissioned and Non-commissioned officers
Lord high admiral or
Admiral of the Navy
Generalissimo or
General of the Armies
Admiral of
the fleet
or
Grand admiral
Field marshal or
General of the army
Marshal of
the air force
Admiral General Air chief marshal
Vice admiral Lieutenant general Air marshal
Rear admiral Major general Air vice-marshal
Commodore Brigadier or
Brigadier general
Air commodore
Captain Colonel Group captain
Commander Lieutenant colonel Wing commander
Lieutenant
commander
Major or
Commandant
Squadron leader
Lieutenant Captain Flight lieutenant
Sub-lieutenant Lieutenant or
First lieutenant
Flying officer
Ensign Second lieutenant Pilot officer
Midshipman Officer cadet Flight cadet
Enlisted grades
Warrant officer or
Chief petty officer
Warrant officer or
Sergeant major
Warrant officer
Petty officer Sergeant Sergeant
Leading seaman Corporal Corporal
Seaman Private Aircraftman
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Sergeant major is a senior non-commissioned rank or appointment in many militaries around the world. In Commonwealth countries, the various degrees of sergeant major are appointments held by warrant officers. In the United States, there are also various grades of sergeant major (command sergeant major, Sergeant Major of the Army, Sergeant Major of the Marine Corps), but they are all of the same pay grade of E–9. (However, the Sergeant Major of the Army and the Sergeant Major of the Marine Corps, as their respective service's Senior Enlisted Advisor, receive a special rate of basic pay that is higher than all other sergeants major.)

In 16th century Spain, the sargento mayor ("sergeant major") was a general officer. He commanded an army's infantry, and ranked about third in the army's command structure; he also acted as a sort of chief of staff to the army's commander.

In the 17th century, sergeant majors appeared in individual regiments. These were field officers, third in command of their regiments (after their colonels and lieutenant colonels), with a role similar to the older, army-level sergeant majors (although obviously on a smaller scale). The older position became known as "sergeant major general" to distinguish it. Over time, the term sergeant was dropped from both titles, giving rise to the modern ranks of major and major general.

The full title of sergeant major fell out of use until the latter part of the 18th century, when it began to be applied to the senior non-commissioned officer of an infantry battalion or cavalry regiment. It is about this time that the U.S. and British histories of the title diverge, with the American Revolutionary War.


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