To bring Vashti the queen - This command, though contrary to Persian customs, is not out of harmony with the character of Xerxes; and is evidently related as something strange and unusual. Otherwise, the queen would not have refused to come.
Related Commentaries of Esther 1:11
Esther 1:11
11 To bring Vashti the queen before the king with the crown royal, to shew the people and the princes her beauty: for she was faird to look on.