Monty Prior was born on Palm Island, to Tom and Emily Prior, after his family had been moved from their traditional lands and sent to the Mission on Palm Island. Prior initially went to a state school but finished his education at a Catholic school and was an altar boy in his early years. At the age of sixteen, Prior was sent off the island to work as a Jackaroo because of an altercation, and his mother passed away before he could return to the Island. Prior worked on cattle stations for eight years before working as a 'navvy', a builder's labourer on civil engineering projects, then as a sugar cane cutter. Prior married Doris Stell in 1947. Prior was ordained in 1982 and became Deacon, serving as assistant Chaplain at Stuart Creek Prison and on the Queensland Aboriginal and Islander Catholic Council. In 1990, Prior and three other Aboriginal Elders travelled to Britain to bring home items of cultural heritage that had been taken from the Mount Morgan area in the 1890s and housed at Glasgow Museum. Prior was also involved with the Central Queensland Land Council, serving as Chairman for almost thirteen years.
Monty Prior is the father of Boori Pryor.