First sergeant

First Sergeant (1SG) is typically a senior non-commissioned officer rank, used in many countries. In NATO armed forces the rank is on OR8 level.

First Sergeant is a specialist in the Singapore Armed Forces. First sergeants are the most senior of the junior specialists, ranking above second sergeants, and below Staff Sergeants. The rank insignia for a First Sergeant features the three chevrons pointing down shared by all specialists, and two chevrons pointing up.

In combat units, First Sergeants are very often platoon sergeants, or given the responsibility for independently operating detachments of support weapons. They are often given instructional billets as well in training schools. First sergeants normally answer to the company sergeant major, assisting the latter in the mentorship, guidance and command of the more junior specialists (Third and Second Sergeants) who are section commanders.

In the United States, a First Sergeant generally serves as the senior enlisted advisor (SEA) of a unit, such as a company, battery, troop, or a USAF squadron or higher level unit. (USA and USMC squadrons and battalions, as well as all higher level units, have a Command Sergeant Major [USA] or Sergeant Major [USMC] as the SEA). (While the specifics of the title may differ between the United States Army, Marine Corps and Air Force, all First Sergeants can be identified by the presence of a lozenge-shaped (colloquially "diamond") figure on their rank insignia.

Historically, the rank of “First Sergeant” has existed in the American Army since 1781, when a fifth sergeant was added to the

table of organization for Continental Army infantry regiments. Previously, under the tables of organization approved by the Continental Congress in 1776 and 1779, there were four and three sergeants, respectively, authorized in each company. The sergeants were numbered in order of seniority and the “First Sergeant” was simply the senior sergeant in the company, but not a separate rank. (Wright, 2006) In 1833, First Sergeant, along with orderly sergeant, became separate pay grades, ranking below Sergeants Major and quartermaster sergeants but above sergeants. While the sergeant major and quartermaster sergeant already had distinctive staff NCO rank insignia, it was not until 1847 that the first sergeant received the lozenge, or diamond, with the three chevrons of a sergeant as his insignia of rank. (The separate rank of orderly sergeant was combined with first sergeant in 1851.) (Perrenot, 2009)

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