Alonzo Barrett was a member of the Lyran Commonwealth Armed Forces, serving with the Third Royal Guards, and a consummate historian. He resigned from the LCAF in 2995 to found his own command, Barrett's Fusiliers. Alonzo had traced his lineage back to a musketeer who served with The Kings Musketeers, a part of the French Royal Guard on ancient Terra, and Alonzo took inspiration from this; members of his command were issued with dress uniforms that consisted of a musketeer's uniform and an epée, and the insignia of the Fusiliers displayed a Musketeer flourishing an epée.
The Fusiliers began as a company of BattleMechs and an AeroSpace Fighter squadron, but grew considerably in size during the Third Succession War. By the time Alonzo and the Fusiliers were involved in the defense of Sevren the command had grown to a full battalion with AeroSpace support, and the Fusiliers augmented that support at Sevren by capturing an Overlord-class DropShip from the 18th Dieron Regulars.
Alonzo would continue to command the Fusiliers throughout the Fourth Succession War, refitting and rebuilding the command after Kingston Caballeros destroyed half the unit on Sabik and leading the Fusiliers back into the fray six months later, joining in the destruction of the 4th Proserpina Hussars on La Blon.
After the Fourth Succession War Alonzo accepted a contract from the Free Worlds League and would continue to command the Fusiliers until his death in 3035. With Alonzo's death, command of the Fusiliers passed to his son, Raul.
- Field Manual: Mercenaries, Revised, p. 42, "Barrett's Fusiliers: The Light Musketeers"