Saint Patrick spent six years enslaved in Ireland.
Patrick’s own autobiographical work, the Confessio, says that Irish raiders captured him when he was sixteen and took him from Britain to Ireland. There he worked as a herder. Patrick describes this period as a profound spiritual turning point: isolated from his family and living in hardship, he says that his faith and practice of prayer grew during his captivity.
After six years, Patrick recounts hearing a voice in a dream telling him that he would soon return home. He escaped, travelled to a ship and eventually made his way back to his family. Later, after years of religious study and preparation, he returned to Ireland as a Christian missionary.
The exact dates and locations of Patrick’s life remain uncertain, and some modern scholars have questioned how literally every detail of the narrative should be read. The duration itself, however, is explicit in the traditional account and is the standard answer to this trivia question. The number is sometimes confused with the age at which he was captured: Patrick was sixteen when taken, but he remained captive for six years.