Did Ezra Form a Jewish Council Called the Great Synagogue?
This is the name of the council, consisting of 120 members, said to have been organized by Nehemiah, about 410 B.C., under the presidency of Ezra, for the purpose of reconstructing the religious life of the returned captives. It is thought to have been a continuing body, governing the returned Jews till about 275 B.C. It is said to have had an important part in gathering, grouping, and restoring the Canonical books of the Old Testament.
Wikipedia. The Great Assembly (Hebrew: כְּנֶסֶת הַגְּדוֹלָה) or Anshei Knesset HaGedolah (אַנְשֵׁי כְּנֶסֶת הַגְּדוֹלָה, "The Men of the Great Assembly"), also known as the Great Synagogue, was, according to Jewish tradition, an assembly of 120 scribes, sages, and prophets, in the period from the end of the Biblical prophets to the early Hellenistic period.Among the developments in Judaism that are attributed to them are the fixing of the Jewish Biblical canon, including the books of Ezekiel, Daniel, Esther, and the Twelve Minor Prophets; the introduction of the triple classification of the oral law, dividing the study of the Mishnah (in the larger sense) into the three branches of midrash, halakot, and aggadot; the introduction of the Feast of Purim; and the institution of the prayer known as the "Shemoneh 'Esreh" as well as the synagogal prayers, rituals, and benedictions.Some modern scholars question whether the Great Assembly ever existed as an institution.