Chronicles and the Book of Kings describe the conquest of the Northern Kingdom by the monarchs of Assyria, Tiglat-Pilesser III (תגלת פלאסר)1 and Shalmaneser V (שלמנאסר)2. The latter, in 722 BCE, took people of Israel into exile:
II Kings chapter 18.11
ויגל מלך-אשור את-ישראל, אשורה; וינחם בחלח ובחבוֹר, נהר גזן–וערי מדי
The king of Assyria took Israel into exile in the land of Assyria; he transported him to Halah, to the Haber, the river of Gozan, and to the towns of Media.
This is one of many cases of forced deportations implemented by the Assyrian Empire, during which many thousands of Jews were exiled to Assyria.
Based on the size and importance of Hamadān as a royal city or capital of the Medes, Vladimir Lukonin3 thinks it reasonable to assume that many of these Jews settled there, making the Jewish community of Hamadān the oldest outside of Israel4.
Benjamin of Tudela5 in his Sefer Massa’ot (מסעות ספר – Travel Book) recounts his visit to Hamadān. He estimates the city’s Jewish population at 50,000 and describes the tomb of Esther and Mordecai.
Shāhin of Shiraz6, a 14th century Persian Jewish poet, recounts, among other stories, in his epic poem Ardashir-Nāmah7, the journey of Queen Esther and Mordechai to Hamadān, where they are said to have died.
Warning: even if it is allowed to drink8 more than usual on Purim, avoid drinking a salmanazar (9-liter bottle) or a nebuchadnezzar (15 liters).
1 Reign 745-727 BCE / 2 Reign 727-722 BCE / 3 Vladimir Lukonin (1932-1984), Russian scholar in the field of ancient Iranian history, culture and arts / 4 The Culture and Social Institutions of Ancient Iran, Lukonin, Cambridge, 1989 (English edition), page 48 / 5 Benjamin of Tudela (circa 1130-1173), rabbi, born in Tudela (Navarre), major figure in medieval Jewish geography and history . / 6 Shāhin-i Shirāzi worked during the reign of Abu Sa’id Bahadur Khan (1316-1335), and was a contemporary of the Persian poet Hafez (circa 1325-1390). / 7 The book of Ardashir or Ahasuerus or Achashverosh, generally identified with Xerxes I (circa 518-465 BCE). / 8 Shulchan Aruch 695.2, Orchot Chaim Halachot Purim note 38.