The Persian king who ruled from India to Cush and whose lavish reign frames the book of Esther. He deposed Queen Vashti for refusing to appear at his banquet, later chose Esther as queen, and elevated Haman as his chief official — only to reverse Haman's genocidal decree once Esther exposed the plot. He honored Mordecai in Haman's place.
Now it came to pass in the days of Ahasuerus, (this is Ahasuerus which reigned, from India even unto Ethiopia, over an hundred and seven and twenty provinces:)Esther 1:1, KJV
Esther 2:17
And the king loved Esther above all the women, and she obtained grace and favour in his sight more than all the virgins; so that he set the royal crown upon her head, and made her queen instead of Vashti.Esther 2:17, KJV
Esther 3:10
And the king took his ring from his hand, and gave it unto Haman the son of Hammedatha the Agagite, the Jews’ enemy.Esther 3:10, KJV
Esther 7:10
So they hanged Haman on the gallows that he had prepared for Mordecai. Then was the king’s wrath pacified.Esther 7:10, KJV
See how Xerxes (Ahasuerus) connects to every other figure in Scripture.