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In the Midrash compilation, Genesis Rabbah, Rabbi Berechiah mentions Ashkenaz, Riphath, and Togarmah as German tribes or as German lands. It may correspond to a Greek word that may have existed in the Greek dialect of the Palestinian Jews, or the text is corrupted from "Germanica." This view of Berechiah is based on the Talmud (Yoma 10a; Jerusalem Talmud Megillah 71b), where Gomer, the father of Ashkenaz, is translated by Germamia, which evidently stands for Germany, and which was suggested by the similarity of the sound.

What are the three German tribes or German lands talked about by Rabbi Berechiah?
Ashkenaz, Riphath, and Togarmah