When did Darwin lose his faith?

Darwin's loss of faith occurred gradually over several years, starting around the time of his famous voyage on the HMS Beagle from 1831 to 1836. He began to question traditional religious beliefs in light of his scientific observations and findings, eventually leading him to reject the notion of a personal god. By the time he published his groundbreaking work "On the Origin of Species" in 1859, Darwin considered himself an agnostic.