The 19th century saw the growth of a number of new movements. The Plymouth Brethren trace themselves back to an evangelical revival on the Powerscourt estate in Co Wicklow and the early preachings of John Nelson Darby, a former Church of Ireland clergyman.

The Seventh Day Adventists were founded by William Miller, who announced that the Second Coming of Christ would take place in 1843, or at the latest by October 1844.

Today, the Plymouth Brethren are generally accepted as part of mainstream evangelical Christianity, although they often remain marginalised. However, other groups which arose in the 19th century put themselves beyond the margins of the Christian tradition with their additional beliefs and books.

The Church of Jesus Christ of Latter Day Saints was founded by Joseph Smith, who claimed he had translated the Book of Mormon in 1844. The movement settled in Salt Lake City in 1847, and is commonly known today as The Mormons.

The Christian Scientists, or the Church of Christ Scientist, was founded in 1879 by Mary Baker Eddy, with a system of beliefs based on her book Science and Health with a Key to the Scriptures.

Later marginal groups would include the Jehovah's Witnesses.

Rev Patrick Comerford is a writer on church history and theology. Contact: theology@ireland.com