By the 6th century, the wise men were referred to as kings in the popular imagination.
This assumption is linked to such prophecies as:

"The Gentiles shall come to your light, and kings to the brightness of your rising." [Is 60,3]

"Kings shall see and arise, princes also shall worship." [Is 49,7]

and

"The kings of Tarshish and of the isles will bring presents; the kings of Sheba and Seba will offer gifts." [Ps 72,10]


The number of kings varied - usually being two, four, or twelve.

Eventually, the number three was settled upon because of the three gifts they bore and the twelve wise men became known as the "Three Kings of the Orient" [Mt 2,11]. They are usually referred to as Caspar, Melchior, and Balthasar.

Furthermore, some people believe each of the wise men came from one of the three continents that were known of at the time of Christ's birth. (See chart below)