Brigade

A brigade is a military unit (usually a grouping of soldiers) used by various military forces in the galaxy.

Dominion

A brigade in the Dominion is comprised of three regiments numbering 6,561 Jem'Hadar and commanded by a Sadok'atorn. (The Dominion War Sourcebook: The Fires of Armageddon)

Klingon Defense Force

A brigade during the Dominion War was roughly comprised of 2,500 warriors and commanded by a 'ech (roughly translates to brigadier general), which was the equivalent of five battalions. (The Dominion War Sourcebook: The Fires of Armageddon)

Romulan Star Empire

A unsha'val is the Romulan equivalent to a brigade and was formed around a group of Al'gess'val (companies) and was around 1,000 soldiers. In the Romulan military a brigade was the unit below a battalion instead of superior as with many other military forces. A unsha'val was commanded by a major. (The Dominion War Sourcebook: The Fires of Armageddon)

The Tal Shiar also used brigades. Trevak served as the first officer of the Special Operations Division's Third Infiltration Brigade from 2372 to 2381. (Star Trek: Remington)

Starfleet Ground Forces

A brigade in the Starfleet Ground Forces is comprised of two to five regiments numbering 5,000 to 20,000 soldiers. A brigade is commanded by a colonel or general. (The Dominion War Sourcebook: The Fires of Armageddon)

Starfleet Marine Corps

A brigade in the Starfleet Marine Corps consists of two or more battalions.

Background

Within the Starfleet Marine Corps of Starfleet International, a numbered brigade corresponds to a region (the fan club equivalent of a numbered fleet).