Born on 29 December 1922 in Canterbury, Victoria, the son of a manager of the Colonial Sugar Refining Company, Weir spent his childhood in Fiji.

[10] Promoted to colonel in 1964 he was appointed deputy director of Military Operations and Plans at Army Headquarters in Canberra, a position he held until 1967.

These operations proved effective and the Viet Cong were unable to mount a major offensive in Phuoc Tuy Province during this time.

By early 1970 the Viet Cong 274th Regiment in the Hat Dich no longer posed a threat to the task force, while D440 and D445 Provincial Mobile Battalions were reported to have left the province.

[14] Weir subsequently settled in Buderim, Queensland, with his wife, and in his later years enjoyed golf, historical research, gardening, painting and writing.