The Rosh was a talmid from the Maharam from Rothenburg who was a talmid of Rav Yitzchak Ohr Zarua of Vienna. He was called Ohr Zarua because of a dream. He saw in a dream that Rebbi Akiva should be spelled with a ‘hey’ at the the end and not an aleph as the last letters of the pasuk ??? ???? ???’ – ?’ ????? indicate. His rebbi was the Sefer Chasidim above, Rebbi Yehudah Hachassid.
