On June 6, 1391, the inhabitants of Seville, Spain, were massacred. Approximately 4000 Jews were killed. From the article:
"Three months later, on June 6, 1391, rioters re-entered the Juderia, blocked the two exits from the quarter, and set it on fire. An estimated 4,000 Jews were killed that day. Most of those who survived converted or left the city, so that by the time of the Expulsion, in 1492, there were few Jews remaining in Seville to be exiled. King Henry III then redistributed the property of the Juderia to various Christian nobles.
The rioting in Seville spread to other parts of Spain – to Castile, Aragon and Catalonia, followed by the island of Majorca. Murderous rioting continued for three months.
The significance of the 1391 rioting goes beyond the toll in life and property: It began a wave of conversions by Jews, estimates of which range between tens of thousands and 200,000 individuals – up to half of the country’s Jews."