The achievements of Rashi and the Baalei Tosfos are all the more astounding when we understand them against the backdrop of the Crusades. Rabbi Wein paints the picture of the fanaticism and violence Jews faced in Europe and the Holy Land alike. Then he gives these events a Halachic context with examples of the Baalei Tosfos' legal rulings regarding the all-to-common problem of the era: Jewish apostasy.