Explanation: The Byzantines protected Western Europe from the Muslims.
The Eastern Roman Empire survived (now called the Byzantine Empire) until 1453, the year of its fall. The period between the fall of the Western Roman Empire and the fall of the Eastern Roman Empire is what we know as the Middle Ages. It was also during this period that there was a diffusion and greater adherence to Christianity, initially among the components of the poorer classes of the population, but also reaching the Roman elites.
