Born: May 4, 1851, Eaton Hall, two miles south of Retford, Nottinghamshire; or Laugharne, Wales (sources differ).
Died: April 24, 1928, Canterbury, England.
Buried: All Saints churchyard, Babworth, England, or Truro Cathedral (Findagrave has two conflicting records),
Arthur was the son of Justice of the Peace George William Mason of Morton Hall, Nottinghamshire, and Marianne Atherton Mitford.
He was educated at Repton School and Trinity College, Cambridge (BA in honors, 1872; DD 1890). He became a Fellow of his college in 1873, and assistant tutor in 1874.
Ordained in 1874, he served as vicar of All-Hallows, Barking, London (1884), and as of 1891 was Honorable Canon and Canon Missioner of Truro, Cornwall.
In 1895 he became Lady Margaret Professor of Divinity at Cambridge, and Fellow of Jesus College. He also served as Master of Pembroke College (1903–12), and Vice Chancellor of the University (1908–10).