The exile of the Jewish people under Ahasuerus was not an accident. According to undefined Rabbah, it was prophesied in detail centuries before it happened, embedded in verses from Isaiah, Jeremiah, and Deuteronomy.
Rav pointed to a verse in Isaiah where God declares: "I will eliminate from Babylonia name and remnant, child and grandchild" (Isaiah 14:22). He mapped each word onto a specific person. "Name" is Nebuchadnezzar. "Remnant" is Evil Merodakh, his successor. "Child" is Belshazzar. And "grandchild" is Vashti, the last link in the Babylonian royal chain, deposed and eliminated in the court of the Persian king. An alternative reading took the verse even further: "name" referred to Babylonia's script, "remnant" to its language. God did not just destroy the dynasty. He erased the civilization.
Shmuel offered a parallel reading from Jeremiah: "I will place My throne in Elam, and I will eliminate king and princes from there, says the Lord" (Jeremiah 49:38). "King" is Vashti. "Princes" are the seven princes of Media and Persia who advised Ahasuerus. Through this lens, God's prophecy targeted not just Babylonia but the entire succession of empires that held Israel captive.
Rabbi Shmuel bar Nahmani then asked a deceptively simple question. Deuteronomy warned that God would send Israel "to a nation unknown to you or your fathers" (Deuteronomy 28:36). But if the exile was to Babylonia, how could it be unknown? Abraham himself came from Ur of the Chaldees in Babylonia. The answer: the verse does not describe Babylonia. It describes Media. The unknown nation, the place Israel had never been before, was the Persian-Median empire of Ahasuerus. And so the opening of the Book of Esther fulfills the Torah's ancient warning: "It was during the days of Ahasuerus."