Rishonim ([ʁiʃoˈnim]; Hebrew: ראשונים; sing. ראשון, Rishon, "the first ones") were the leading rabbis and poskim who lived approximately during the 11th to 15th centuries, in the era before the writing of the Shulchan Aruch (Hebrew: שׁוּלחָן עָרוּך, "Set Table", a common printed code of Jewish law, 1563 CE) and following the Geonim (589-1038 CE). Rabbinic scholars subsequent to the Shulkhan Arukh are generally known as acharonim ("the latter ones").
The distinction between the rishonim and the geonim is meaningful historically; in halakha (Jewish Law) the distinction is less important. According to a widely held view in Orthodox Judaism, the acharonim generally cannot dispute the rulings of rabbis of previous eras unless they find support from other rabbis in previous eras. On the other hand, this view is not formally a part of halakha itself, and according to some rabbis is a violation of the halakhic system. In The Principles of Jewish Law, Orthodox rabbi Menachem Elon writes that:
Abba Mari, (Minhat Kenaot), 13th century Provençal rabbi
Don Isaac Abravanel, (Abarbanel), 15th century philosopher and Torah commentator
Israel Bruna, (Mahari Bruna), 15th century German Rabbi and Posek
Abraham ibn Daud, (Sefer HaKabbalah), 12th century Spanish philosopher
Abraham ibn Ezra, (Ibn Ezra), 12th century Spanish-North African Biblical commentator
David Abudirham, said to be a student of the Baal Ha-Turim (but this is doubtful)
Samuel ben Jacob Jam'a, 12th century North African rabbi and scholar
Asher ben Jehiel, (Rosh), 13th century German-Spanish Talmudist
David Kimhi, (RaDaK) 12th century French biblical commentator, philosopher, and grammarian
Yaakov ben Moshe Levi Moelin, (Maharil), 14th century codifier of German minhag
Obadiah ben Abraham of Bertinoro, (Bartenura), 15th century commentator on the Mishnah
Bahya ibn Paquda, (Hovot ha-Levavot), 11th century Spanish philosopher and moralist
Hasdai Crescas, (Or Hashem), 14th century Talmudist and philosopher
Dunash ben Labrat, 10th century grammarian and poet
Rabbenu Gershom, 11th century German Talmudist and legalist
Gersonides, Levi ben Gershom, (Ralbag), 14th century French Talmudist and philosopher
Eliezer ben Nathan, 12th century poet and pietist
Hillel ben Eliakim, (Rabbeinu Hillel), 12th century Talmudist and disciple of Rashi
Ibn Tibbon, a family of 12th and 13th century Spanish and French scholars, translators, and leaders
Isaac Alfasi, (the Rif), 11th century North African and Spanish Talmudist and Halakhist; author of "Sefer Ha-halachoth"
Jacob ben Asher, (Baal ha-Turim ; Arbaah Turim), 14th century German-Spanish Halakhist
Joseph Albo, (Sefer Ikkarim), 15th century Spain
Joseph ibn Migash 12th century Spanish Talmudist and rosh yeshiva; teacher of Maimon, father of Maimonides
Meir Abulafia, (Yad Ramah), 13th century Spanish Talmudist
Maimonides, Moshe Ben Maimon, (Rambam), 12th century Spanish-North African Talmudist, philosopher, and law codifier
Mordecai ben Hillel, (The Mordechai), 13th century German Halakhist
Nahmanides, Moshe ben Nahman, (Ramban), 13th century Spanish and Holy Land mystic and Talmudist
Nissim of Gerona, (RaN), 14th century Halakhist and Talmudist
Rashi, (Solomon ben Yitzchak), 11th century Talmudist, the primary commentator of Talmud
Elazar Rokeach, (Sefer HaRokeach), 12th century German rabbinic scholar
Samuel ben Judah ibn Tibbon, 12th-13th century French Maimonidean philosopher and translator
Tosafists, (Tosafot), 11th, 12th and 13th century Talmudic scholars in France and Germany
Yehuda Halevi, (Kuzari), 12th century Spanish philosopher and poet devoted to Zion
Menachem Meiri, (Meiri), 13th century Talmudist
Yom Tov Asevilli, (Ritva), 13th century Talmudist
Yitzhak Saggi Nehor, (Isaac the Blind), 12th-13th century Provençal Kabbalist
Solomon ben Aderet, (Rashba), 13th century Talmudist
Aharon HaLevi, (Ra'ah), 13th century Talmudist
Zerachiah ha-Levi of Girona, (Baal Ha-Maor) 12th century Talmudist
Meshullam ben Jacob, (Rabbeinu Meshullam Hagodol), 12th century Talmudist
Joseph Caspi, 13th–14th century talmudist, grammarian, and philosopher
Rishonim Wikipedia (Text) CC BY-SA