At the dawn of the 16th century, both Ashkenazi and Sephardi Jews relied on oral traditions of Jewish law - Halakha. Both groups passed down their own unique customs. However, after the Spanish Inquisition’s mass expulsion, Sephardic Jews found themselves living alongside the Ashkenazi Jews of Eastern Europe. This led to confusion over which traditions and laws to follow. Though they would never meet, Rabbi Yosef Karo and Rabbi Moses Isserles (AKA the “Rema”) worked together to create a book that would continue to shape Jewish practice for the next 500 years and counting.