The pair were engaged in Anne’s youth. When Percy mentioned this arrangement to Cardinal Wolsey (to whom he was an aide at the time), Wolsey protested, according to George Cavendish:
“I am amazed at your foolishness in getting entangled, even engaged, to this silly girl at court – I mean Anne Boleyn. Have you not considered your position? After the death of your noble father you stand to inherit one of the greatest earldoms in the country. It would thus have been more proper if you had sought the consent of your father in this affair and to have made his Highness the King privy to it, requesting his royal blessing. Had you done so, he would not only have welcomed your request but would, I can assure you, have promoted you to a position more suited to your noble estate. And thence you might have gained the King’s favor by your conduct and wise council and and thus risen further still in his estimation.
But now look what you have done by your thoughtlessness. You have not only offended your own father but also your sovereign and pledged yourself to someone whom neither would agree to be suitable. And do not doubt that I shall send for your father and when he comes he will break off this engagement or disinherit you forever. The King himself will make a complaint to your father and demand no less an action than I have suggested. Indeed, I happen to know that the King has already promised this lady to someone else and that though she is not yet aware of it, the arrangements are already far advanced. The King however, being a man of great prudence and diplomacy, is confident that, once she is aware of the situation, she will agree to the union gladly.”
The person that Anne was promised to was Henry VIII. When the King thought she would have no objection, he was taking a pretty big leap of faith, there.