The Journey of the Magi
Intrigued by the rising of a star, which they associated with the king of the Jews, astrologers came to the capital city of the Jews for more information. Directed to Jesus, these Gentiles worshipped him offering gifts of gold and frankincense and myrrh.
Tradition came to associate the magi with Persia. Matthew does not say how many there were, but because three gifts are mentioned, tradition quickly settled on the number three. Eventually they were elevated to royalty (three kings), and by the sixth century had names [in the west known as Balthasar, Melchior and Gaspar]. Much later Balthasar appeared in art as black, as shown in this panel.