 He was also Assistant Bishop of Oxford until 1939, when the suffragan See of Dorchester was created for him, and to make permanent the assistance he provided the Bishop diocesan.The suffragan See was erected by Order-in-Council (under the Suffragans Nomination Act 1888) on 2 February 1939 and Allen was nominated to it by Letters Patent dated 27 February.Because of his scholarly qualifications,he was seriously considered for several diocesan bishoprics in England,including Guildford in 1934,Portsmouth in 1941 and Gloucester in 1945.