Jesper

Jesper is a Danish form of Jasper that is also used in Swedish and Norwegian. The wider Jasper and Gaspar family is commonly connected with an old word for treasurer, probably reaching back through Hebrew to Persian. Because that route is proposed rather than fully certain, “possibly treasurer” is the careful interpretation.

The name family became familiar in Christian Europe through the traditional naming of one of the Magi as Caspar or Gaspar. Those names come from later tradition rather than the biblical text itself. Jesper gives that long-established family a northern European form, alongside Kasper and Casper. Its initial j normally follows the sound conventions of the language using it, which can surprise an English reader who knows Jasper first.