About This Unit
The South Australian 4th Garrison Brigade was the headquarters for the 4th and the 18th Garrison Battalions within the 4th Military District (SA) and was responsible for all administrative work of the Garrison Battalions. It was raised in 1941 and disbanded in 1942.
The Brigade over saw the command of the following Garrison Battalions:
The 4th Garrison Brigade was the first Garrison Brigade to be established in Australia. It was numerically named after the military district that it fell under; that being South Australia which was classed as the 4th Military District. Its first and only commanding officer was Lieutenant Colonel John Morphett Irwin who had previously commanded the 4th Garrison Battalion. The 4th Garrison Brigade was established to overlook both the 4th and 18th Garrison Battalions in South Australia and their operations. In 1942, however, when the 18th Garrison Battalion was disbanded due to lack of personal the 4th Garrison Brigade was no longer required and as such it was also disbanded.
Although the 25th Garrison Battalion and the 33rd Garrison Battalion (later the 25/33rd Garrison Battalion after their amalgamation together) were also based in South Australia these Garrison Battalions were never directly under the command of the 4th Garrison Brigade.