Was Christian a proper name before Pilgrim's Progress?

I was going to ask this on Christianity.SE but it's not really a Christian Doctrine question; hope it fits here.

I was reading John Bunyan's Pilgrim's Progress where almost everyone is named for a virtue or a vice except the protagonists (Christian and Christiana). Were those names common at the time of Bunyan or was he the first to use them as a proper name?

Behind The Name says it was in use in the Middle Ages, but didn't become popular until the 17th century, so the rise in popularity could conceivably be tied to Pilgrim's Progress.

There were also 10 Danish kings with the name Christian, the first born in 1426. So definitely the use of the name predates Bunyan.