What pen name did C.S. Lewis use for The Pilgrim’s Regress?

C.S. Lewis used the pen name Clive Hamilton for The Pilgrim’s Regress. The allegorical book was published in 1933 and was his first book of Christian apologetics.

The title alludes to John Bunyan’s The Pilgrim’s Progress, but Lewis’s work is not a sequel. It follows a character named John as he travels through an imaginative landscape while wrestling with philosophy, culture, and religious belief. Lewis wrote the book after his conversion to Christianity and used it to explore the intellectual path that had led him back to faith.

Lewis later published most of his major works under the name C.S. Lewis. The pseudonym Clive Hamilton is therefore strongly associated with The Pilgrim’s Regress, while his science-fiction trilogy appeared under his familiar initials. The surname Hamilton came from his mother’s family, making the pen name distinct from his legal name.