The Catholic Church in the Isle of Man is part of the worldwide Catholic Church, under the spiritual leadership of the Pope in Rome.
Although not part of the United Kingdom, for geopolitical reasons the Isle of Man is part of the Archdiocese of Liverpool. There are Catholic churches in all of the main towns, the largest being St. Mary of the Isle in Douglas. A large percentage of the Roman Catholics on the Isle of Man are Irish or of Irish descent.
Following the English Reformation the allegiance of the Manx church to Rome was broken and Catholic practices forbidden. The running trade however brought trading links with Ireland, France and other Catholic countries thus providing a nucleus for a small Catholic community.
At its most anti-Roman Catholic period the English penal code stipulated perpetual imprisonment for saying Mass, declared Catholics incapable of purchasing or inheriting land and made the possession of a horse worth more than £5 a criminal offence. The Island did not follow these practices - until quite late in Elizabeth's reign the Earls of Derby were Catholic and did little to spread the reformation to the Island where it progressed relatively slowly. Though the Island displayed considerable religious toleration (however around the 1660s a small group of Maughold Quakers was persecuted) and had none of the penal laws about Catholics that so disfigured the English Statute book, they were of course required to obey the ecclesiastical laws of attendance at church, places of marriage and burial etc. (several Catholic priests were briefly imprisoned in the 18th century for illegally celebrating marriage), another was presented in 1759 for attending a non-Catholic.
From 1779 a Benedictine monk, Father Johnston, who served the mission at St. Begh's Whitehaven, started to make regular pastoral calls - he noted some 29 Catholics living on the Island. In 1789 an émigré priest, Father Louis, sought asylum on the Island; for a time he acted as tutor to the governor's and bishop's children whilst living at Castle Rushen. He would offer Mass in a barn at Scarlett or at the cottage of some Catholic family. He appears to have left the Island before 1794. Around the early 19th century an influx of Irish, fleeing the Irish rebellion of 1798, brought the number of Catholics up to around 200. One of these families, the Fagans, brought over their chaplain, Father Collins, who until his death in 1811 seems to have ministered to the Irish fishing community of Castletown. He is buried near St. Michael which appears to have been regularly used as a chapel.