Born in Rhodesia, (the mildly offensive "Rhodesian born, Rhodesian bred, strong in the arm, thick in the head" has a ring of truth to this one) Reid-Daly entered military service in 1951 and served with C (Rhodesia) Squadron of the British SAS in operations against Malayan insurgents. Rising to the rank of RSM in the RLI, he was later commissioned and achieved the rank of Captain. He retired from the Army in 1973, but Peter Walls, then chief of the Rhodesian Army, persuaded him to return to active duty in order to form the Selous Scouts

Through the war, whilst the Scouts achieved many of their military objectives, their unorthodox methods - not simply their lack of uniform, and essential refusal to follow standard disciplinary procedures - created tensions within the military hierarchy. Reid-Daly had several brushes with the Rhodesian authorities. In 1979 charges were laid against Reid-Daly for using Scouts for ivory poaching and weapon smuggling. Whilst defending himself against these charges (which may well have been founded on some truth), Reid-Daly verbally attacked General (sometimes noted as Lieutenant-General) John Hickman. For this he was charged with insubordination and sentenced with a reprimand; essentially a charge which served less as a punishment, merely obeying formalities. Following his move in 1982 to South Africa, he was to command the Transkei Defence Force. (At this time, Transkei was one of the allegedly "independent black home-lands" within apartheid South Africa's borders - many of the TDF members had already been trained in Rhodesia).