Roger Beresford Steadman was born in Bridgenorth, Shropshire on 27 August 1938, the son of Clifford Stuart Steadman and Ida Naomi Steadman (née Greenslade). He joined the Royal Navy as a Cadet at the Britannia Royal Naval College, Dartmouth, on 1 January 1956 and was promoted to Acting Sub Lieutenant on 1 September 1957. He was further promoted to Lieutenant on 1 January 1960.

The 1960 Navy List records an appointment to HMS TURPIN. He was married to Christine Sallie Steadman (née Child) and their marriage was registered in the Surrey Northern District for the 1st Quarter of 1961. The 1962 Navy Lists notes that he was still serving in TURPIN. He was next appointed to the Submarine Depot Ship HMS AMBROSE (Sixth Submarine Squadron at Halifax, Nova Scotia). He had returned home to UK by 1965 and is understood to have been serving in HMS DOLPHIN.

Roger Steadman of Lammas Cottage, The Tilt, Cobham, Surrey is reported to have died in the Princess Mary RAF Hospital, Wendover, Buckinghamshire, on 21 March 1965. The cause of his death is not stated but it is recorded in the Aylesbury, Buckingham Registration District. Roger Steadman is buried in the Cobham Cemetery.