The 1st Light Horse (Machine Gun) Regiment (Royal New South Wales Lancers) was renamed the 1st Machine Gun Regiment in December 1941. In March 1942, the regiment was again renamed, being converted to the 1st Motor Regiment. This change was short lived however, and it was changed again in May to the 1st Tank Battalion, becoming part of the Australian 3rd Army Tank Brigade, equipped with Matilda tanks. In 1943 the unit became part of the 4th Armoured Brigade and was designated as an AIF unit, thus allowing it to be deployed to any theatre of the conflict, and it deployed to New Guinea in August 1943 and fought against the Japanese in the Battles of Sattelberg and Lakona. The unit was then withdrawn to Australia in mid-1944. On 1 June 1944, the unit was renamed the 1st Armoured Regiment, and in May 1945, it took part in the amphibious landings at Balikpapan in support of the 7th Division, being involved in one of the final Australian campaigns of the war in Borneo.