Esther 3:5-7

And when Haman saw that Mordecai bowed not down, nor did him reverence, then was Haman full of wrath. But he thought scorn to lay hands on Mordecai alone; for they had made known to him the people of Mordecai: wherefore Haman sought to destroy all the Jews that were throughout the whole kingdom of Ahasuerus, even the people of Mordecai. In the first month, which is the month Nisan, in the twelfth year of king Ahasuerus, they cast Pur, that is, the lot, before Haman from day to day, and from month to month, to the twelfth month, which is the month Adar.