Jamieson, Fausset and Brown on Esther 9:5-16

5-16. Thus the Jews smote all their enemies--The effect of the two antagonistic decrees was, in the meantime, to raise a fierce and bloody war between the Jews and their enemies throughout the Persian empire; but through the dread of Esther and Mordecai, the provincial governors universally favored their cause, so that their enemies fell in great numbers.