Yitzchak ben Asher Halevi (Riva) was one of the first Ba'alei HaTosafot. He lived in Speyer and was a student of Rashi. He also seems to have studied with Rashi's teacher, R. Yitzchak ben Yehudah, and, after Rashi's death, with Rashi's son-in-law, R. Meir ben Shmuel. His grandson, bearing the same name, died a martyr's death in Speyer in 1196 during a pogrom instigated by a blood libel. He was given great respect by the leading sages of his generation, and was renown for his piety and asceticism.