Smith's Bible Dictionary
(a star). The Persian name of Hadassah. (myrtle),
daughter of Abihail, the son of Shimei, the son of Kish, a Benjamite.
Esther was a beautiful Jewish maiden. She was an orphan, and had been
brought up by her cousin, Mordecai, who had an office in the household
of Ahasuerus, king of Persia -- supposed to be the Xerxes of history --
and dwelt at "Shushan, the palace."
When Vashti was dismissed from being queen, the king chose Esther to the place, on account of her beauty, not knowing her race or parentage; and on the representation of Haman, the Agagite, that the Jews scattered through his empire were pernicious race, he gave him full power and authority to kill them all.
The means taken by Esther to avert this great calamity from her people and her kindred are fully related in the book of Esther. The Jews still commemorate this deliverance in the yearly Festival of Purim, on the 14th and 15th of Adar (February, March). History is wholly silent about both Vashti and Esther.
Taken from: Smith's Bible Dictionary by Dr. William Smith (1884)