Following the death of her husband in February 1896, a few weeks after her son's [J.R.R.'s] fourth birthday, Mabel Tolkien... became passionately devoted to Christianity, taking her two sons every Sunday on a long walk to a "high" Anglican church. Then one Sunday they were taken by strange roads to... St Anne's, a Roman Catholic church... Mabel Tolkien had been considering conversion for some time, and during the spring of 1900 she received instruction and was received in June of the same year... Her conversion incurred the immediate wrath of her family. Her father, who had been brought up Methodist but had since lapsed... into Unitarianism, was outraged. Her brother-in-law withdrew the little financial help that he had provided since she had become a widow, plunging her and her children into poverty. She also met with considerable opposition from her late husband's family, many of whom were Baptists with strong anti-Catholic prejudices. The emotional strain affected her health adversely but, undaunted, she began to instruct her sons in the faith. Tolkien made his First Communion at Christmas, 1903... Less than a year later his mother died after lapsing into a diabetes-induced coma."
From: "Religious Affiliations of Celebrities" page in "Celebrity Religion" section of "Religion Facts" website (http://www.religionfacts.com/celebrities/religions_of_celebrities.htm; viewed 26 April 2007):
Below is an index of the religious affiliations or belief systems of celebrities (both living and dead; in film, television, music, literature, academics and politics), listed in alphabetical order by last name...
Celebrity: J.R.R. Tolkien
Religion/Belief: Catholicism
Quotes, More Information, Sources:
The author of the Lord of the Rings was a devout Catholic for most of his life. He played a significant role in the conversion of his friend C.S. Lewis.