The 3 Kings
It's verifiable by checking the N.T. text that they were called "wise men", not kings, and no number is specified. Apparently there was, early on in the history of Christianity, the assumption that there were three of them because three gifts are mentioned. Also, there seems to have been the assumption that they were kings because the gifts were extraordinarly costly (and the journey would have been a huge expense). I'm not sure when/where the names were made up; Google might help.