Eliezer ben Natan (Ra'avan) was a German rabbi, posek and commentator. His contemporaries and successors refer to him as an authoritative transmitter and decisor of Jewish tradition and practice. Among his descendants and relatives were some of the great rabbinic figures of the next generations. He was one of the first Ashkenazic scholars to quote extensively from the Talmudic commentary of Rabbeynu Chananel. He was also the first German scholar to pen commentaries on piyyut (liturgical poetry).