Rabbenu Avigdor ben Rabbenu Eliyahu HaKohen Katz a tosafist born is Austria, functioned as Rabbi in Vienna. His brothers where Rabbenu Eliezer HaKohen and Rabbenu Shneur of Neustadt.
A talmid of Rabbi Simcha of Speyer and Rav Elazar ben Shmuel of Verona – apparently his brother in law – Rabbenu Avigdor later penned a commentary to nevi’im and ketuvim. His commentary to Shir HaShirim has been printed.
Rabbenu Avigdor was also an avid writer of responsa of which are quoted often by the Mordechai, Hagahot Maymoniyot and the Shibulei Leket.