When Alexander the Great decisively defeated King Darius III at Issus in 333 BC, he captured the Persian king’s wife, mother, and two daughters. Over the next few years, Darius III tried to both ransom back his family and negotiate a peace:
Darius, panic-stricken at the fate of his picked troops, wrote offering Alexander his daughter in marriage and half his kingdom.
“Were I Alexander,” advised the Macedonian counselor, Parmenion, “I should avoid further risk by accepting these terms.”
“Were I Parmenion,” retorted the young invader. “I should do the same. But I am Alexander. Write this to Darius: ‘You offer me part where I am lord of all. If I choose to marry your daughter, I shall do so whether you are willing or not.’
The World’s Great Events, 1908, by Albert Payson Terhune.
And onward Alexander marched. He wed the proffered daughter, Stateria, in ~324 BC, nine years later.
While historians debate both the accuracy and timing — wikipedia states that “conflicting reports… make the peace negotiations hypothetical” — the confidence and arrogance seem accurate.