John William Wall (6 November 1910 – 11 April 1989), pen name Sarban, was a British writer and diplomat. Wall's diplomatic career lasted more than thirty years, but his writing career as Sarban was brief and not prolific, ending during the early 1950s. Sarban is described in The Encyclopedia of Fantasy as "a subtle, literate teller of tales, conscious of the darker and less acceptable implications that underlie much popular literature". Wall cited the supernatural fiction of Arthur Machen and Walter de la Mare as influences on his work.
Wall was born in Mexborough in Yorkshire, the son of George William Wall, a passenger guard on the Great Central Railway, and Maria Ellen (née Moffatt) Wall. After Mexborough School, he studied English at Jesus College, Cambridge and received first-class honors. He also studied Arabic and took the Consular Service Examination.
Wall married Eleanor Alexander Riesle on 20 January 1950 and they had one daughter. Wall and his wife were separated legally during 1971.
He chose a diplomatic career in the Near East because "[James Elroy] Flecker, whose poetry I had loved in my school days, had been in the Levant Consular Service", and owing to "a liking for travel and oriental philology". During 1933, Wall was posted initially as Probationer Vice-Consul at Beirut, Lebanon. Subsequently, he was stationed at Jeddah in Saudi Arabia, Tabriz and Esfahan in Iran, and Casablanca in Morocco. He was posted as the first Political Agent to the Trucial States in Dubai following the relocation of the seat of British representative from Sharjah to Dubai in 1953. After WWII, he was Counsellor at the British Middle East Office in Cairo until 1952. He was British Ambassador to Paraguay 1957-8 and Consul-General at Alexandria 1963-5. He was honoured in 1953 as a Companion of the Order of St Michael & St George for his diplomatic work.
Wall continued to work for the Foreign Office, at first in a teaching position in London, 1966–1970, and then at the Government Communications Headquarters, a secret surveillance centre, in Cheltenham.