1970 – Became the 6th Archbishop of Brisbane.
– Arnott presided at a time of experiment within the Church of different forms of liturgy.
1977-1978 – He introduced An Australian Prayer Book.
– He was a member of the Anglican Roman Catholic International Commission and was an ardent mover for reunion with Rome.
– Arnott was pro-ordination of women and deeply concerned with perceived erosion of civil liberties.
1980 – He retired from being a bishop.