John Bradburne was abducted from a leper colony and accused of being a spy for the white regime by guerrilla fighters during Zimbabwe's civil war.
He was shot in the back after refusing to abandon the leprosy community where he worked to prevent exploitation in 1979, just three months before the country's conflict ended.
A formal decree has now been issued by the Vatican to begin the process of Mr Bradburne's canonisation.
A ceremony will be held on September 5th, at the Zimbabwean leper colony where he served, to recognise his missionary influence on the 40th anniversary of his death.
Mr. Bradburne settled in the Mutemwa colony in Harare after 16 years of travel, calling himself "a strange vagabond of God", two years before the countries liberation war broke out in the former Rhodesia.
He is said to have confided to a Franciscan priest that he had three wishes; to serve leprosy patients, to die a martyr, and to be buried in the habit of St Francis.
Numerous healings have been informally attributed to his intercession, including a man in Scotland cured of a brain tumour and a South African woman regaining the use of her legs.
Mutemwa has now become a place of pilgrimage, seeing up to 25,000 Zimbabweans gathering to remember the work of Mr Bradburne each year.
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