In 2021-2024, I received an ISF grant to research the extent of rabbinic activity in medieval Paris and its close environs. The project aimed to better understand the relationship between Paris and developments in rabbinic thought elsewhere in the region (Champagne, Normandy, England, Rhineland, eastern Germany, Provence and Languedoc). I also hoped to identify the independent and distinctive aspects of Halakhah as it developed in medieval Paris that bear some connection to its unique environment as a very large metropolis, the seat of the French kingdom and home to one of the most important and innovative universities in Europe.

One product of this research project was an MA thesis by Rachel Eilon Kochva titled "Rabbi Judah Sir Leon of Paris: Studies in His Tosafot to Berakhot" (Bar-Ilan University, 2024).

The following articles, prepared as part of this project, have been published:

1. ‘La médiation dans l'Orléans médiéval: Le Responsum 241 de Rachi’, Tsafon: Revue d’études juives du Nord 90 (2025): 37-48
2. ‘Contacts between French and English rabbis during the Twelfth and Thirteenth Centuries’, Revue des études juives 184 (2025): 83-97
3. ‘“It Requires Privacy”: Sharing a House in Thirteenth-Century Paris’, Jewish History 38 (2024): 1-17