He was brought up in Somerset, although he was said to be proud of his Welsh descent. He served as a regular soldier in the Somerset Light Infantry during the Malayan emergency, the Suez Crisis, and the EOKA campaign in Cyprus.

He taught in Catholic schools for thirty years until retiring in 1992 to take up writing full time. Initially, he supported the French Archbishop Marcel Lefebvre, founder of the Society of St. Pius X, but was critical of the latter's decision to consecrate four bishops in 1988 against the wish of Pope John Paul II. Davies was head of the international Traditional Catholic organisation Una Voce.