In the year of 1259, after a run of bad weather in Italy, harvests failed and famine spread across the peninsula. Thousands of religious fanatics known as Flagellants took to the highways and byways, leading processions through towns and cities, whipping themselves into frenzies of self-harm. The movement was sparked by a letter reputedly sent from heaven via an angel. It contained a dire warning – that widespread neglect of the Sabbath had infuriated the Lord. In consequence, the world was being punished with a series of natural calamities, prompting food shortages, plague, war, and death. Indeed, the end of the world was in view, unless the faithful shaped up and got back to church.