Meir ben Shmuel was a French rabbi and one of the early Baa'lei HaTosfot. He was one of the founders of the Tosafot school and approach to Talmudic commentary. He was a son-in-law of Rashi, and three of his sons, Rashbam, Rivam and Rabbenu Tam, were amongst the greatest talmudists and tosafists, as well as leaders of their generation.