Born in Marylebone, London on 28 July 1870, he was ordained to the priesthood on 2 February 1893 at Westminster, after which he acted as chaplain at the Visitation at Harrow.
[1] He received his episcopal consecration on the following 25 February from Cardinal Francis Bourne, Archbishop of Westminster, with Bishops Peter Amigo of Southwark and William Cotter of Portsmouth serving as co-consecrators.
Dunn found a rapidly growing diocese and encouraged church building on an unprecedented scale.
The first stone of the Church of the Holy Spirit in West Bridgford was laid by Bishop Thomas Dunn in 1929.
[2] He introduced the daily recitation of the Divine Office by the Cathedral clergy and gave a more prominent place to the use of plainchant in the liturgy.