the diocese of exeter is a diocese of the church of england including the whole of devon, and it is one of the largest in england. the head of the diocese is the bishop, michael langrishe, and the cathedral is in the city of exeter. it is part of the province of canterbury. two other bishops and four archdeacons help the bishop of the diocese oversee all the anglican parishes and congregations of devon. there are 506 parishes in this diocese. before the founding of the diocese of truro in 1876 the whole of cornwall was also part of the diocese of exeter.