They saw the star of Jacob.
The prophecies of the Prophet Daniel had now come true in Elam-Persia and the wise men set out on their mission from the three great nations of the Earth to follow that star to Jerusalem, where they knew that the King of Kings was to be born into our World.
Tradition places them at the end of the Christmas story, but they had traveled over a two year period to reach our Lord and they by tradition may have come from Ethiopia, China and India to present these precious gifts to the King child?
Numbers 24:17, Matthew 2:1-10, Revelation 22:16.