in 1921, australia's part-time military force was reorganised. where possible an effort was made to raise battalions in the locations from where they had drawn the majority of their personnel during the war. as a result, the battalion was reformed at this time at subiaco in western australia, however, the following year it was moved to launceston, tasmania, and then to sydney, in 1924, where it was attached to the 8th brigade, which was part of the 1st division. in 1927, the battalion was regimented as 51st battalion, field of mars regiment. during its period in new south wales, as a result of austerity measures imposed upon the military due to the economic hardships of the great depression and the lack of manpower that resulted from the end to compulsory service, the battalion was twice amalgamated, firstly with the 30th battalion in 1930, then with the 18th battalion on 1 july 1935. in 1936, the two battalions were unlinked and on 1 october, the 51st battalion, far north queensland regiment was re-raised at cairns, queensland, taking on the lineage from the original 51st battalion. at this time major (later lieutenant colonel) hubert harris was appointed commanding officer of the battalion.