Reginald was born at Eton Place in 1892, the second son of Mary Richardson Reid and Reginald Barrett Pope, a Brighton solicitor and former churchwarden of St Mary's. His parents later lived at The Cliff, Blackrock, Brighton. His father died in 1913 aged 56 and his mother died in 1921. He had three sisters and two brothers, one of whom was also killed in the First World War.
He was educated at Brighton College (Junior House) between 1901 and 1904 before proceeding first to Rottingdean School and then to Bradfield College where he was a keen cricketer. After Bradfield he went to the RMC Sandhurst in 1911 where he graduated 23rd in his cohort of cadets and received a commission as Second Lieutenant in the Welsh Regiment on September 23rd 1911.