Daniel 1:3 & 4
Then the king ordered Ashpenaz, chief of his court officials, to bring in some of the Israelites from the royal family and the nobility - young men without any physical defect, handsome, showing aptitude for every kind of learning, well informed, quick to understand, and qualified to serve in the king's palace. He was to teach them the language and literature of the Babylonians.
Along with other treasures was taken the best and the brightest of the children from the royalty of Judah. The purpose was to teach them to serve as slaves in the palace. This was a matter of pride in that, when people visited the king, they would see that the best and the brightest of Israel were brought down to the level of slavery by King Nebuchadnezzar.