Having discussed the general context of the book of Esther and Vashti’s importance in it as well as some of the background to Vashti’s introduction, let’s take a closer look at the verse preceding her denial of the king’s request:
On the seventh day, when the heart of the king was merry with wine, he commanded Mehuman, Biztha, Harbona, Bigtha and Abagtha, Zethar and Carkas, the seven eunuchs who served in the presence of King Ahasuerus.
Esther 1:10 (ESV)
Of course, “merry with wine” is a euphemism for being inebriated to some extent. However, the king’s blood-alcohol level aside, the context of the passage (not to mention the rest of the book) makes it clear that the king was drunk on power, patriarchy, pride as well as alcohol.