Peter Hugh Brown was born in Greymouth, New Zealand. He is the youngest child born to William and Mary (Sweeney) Brown. His primary and secondary education was with the Marist Brothers. He entered the regular work-force before he began religious formation. Brown professed first vows as a Redemptorist on February 16, 1969 and perpetual vows on October 26, 1975.  For 7 years Brown was a professed religious Brother in the congregation working in the different community and later assigned to Samoa to help out at the mission. After been a brother in the congregation he studied for the priesthood at Yarra Theological Union in Melbourne, Australia. 

Brown was ordained a priest by Bishop Brian Ashby of Christchurch on December 19, 1981. He served as a missionary on Savaii Island, Safotu, as a chaplain in the office of chaplain for migrants in Auckland, New Zealand, and as a parish priest in Clover Park, South Auckland before he was elected as the Redemptorist's regional superior.  Brown is fluent in the Samoan language.  Pope Francis named Brown the bishop of Samoa-Pago Pago on May 31, 2013. On August 22, 2013, Brown was ordained by Archbishop Martin Krebs, Apostolic Nuncio to New Zealand, Cook Islands, Federated States of Micronesia, Kiribati and Palau. The principal co-consecrators were Bishops John Quinn Weitzel, M.M., Bishop Emeritus of Samoa-Pago Pago, and Denis George Browne of Hamilton, New Zealand.

Following the aftermath of Cyclone Gita in 2018, the Diocese has undergone several repair and renovation projects to fully restore Diocesan facilities to serve our church community.