Patrick (c. 389- c. 461) was a famous Celtic missionary to Ireland. Patrick (or, more correctly, Patricius) was captured at the age of 16 by pirates and was sold into slavery to sheepherders in Northern Ireland.
Clive Staples (C. S.) Lewis (1898-1963) was born in Belfast, Ireland and educated at Oxford. He was a professor of medieval and Renaissance literature at Cambridge.
John Nelson Darby (1800-1882) was the founder of the Plymouth Brethren.
Adam Clarke (c. 1762-1832) was a Methodist minister, commentator, and theologian. He was born in Ireland and, after receiving a very limited education, was apprenticed to a linen manufacturer.
Amy Carmichael (1867-1951) was born in Northern Ireland and educated at Wesleyan Methodist Boarding School. She grew up in a wealthy and well-connected family. Yet, despite her privileged circumstances, she dedicated her life to missions and went to Japan in 1893.