Rabbi Yaakov ben Meir of Romereau (1100?-1171), known as "Rabbeinu Tam", was a grandson of Rashi (Rabbi Shlomo Yitzchaki, 1040-1105), and one of the primary authors of the Tosaphot commentary on the Talmud; the Bet-Din (rabbinical court) he headed was regarded as the leading Torah authority of his generation.

Links:
Rabbeinu Tam (Rabbi Yaakov ben Meir)

Rabbi Meir ben Baruch ("Maharam") of Rothenburg (1215?-1293), the great Talmudic commentator and leading Halachic authority for German Jewry, was imprisoned in the fortress at Ensisheim. A huge ransom was imposed for his release. The money was raised, but Rabbi Meir refused to allow it to be paid lest this encourage the further hostage taking of Jewish leaders. He died in captivity after seven years of imprisonment.

Link: Maharam (a brief biography)