August 2, 1492. The date by which all Jews in Spain had to leave the country. OK, maybe it was July 31 – the historical record is not exactly clear, and our calendar-keeping has changed since then. Either way, it was close enough to Tisha B’Av for the event to be associated with the date.
Tisha B’Av is our all-purpose mourning day. The early rabbis assigned all manner of disasters that befell our ancestors to that date, beginning with the destruction of the First Temple in Jerusalem, and then the Second, and the crushing of the Bar Kochba rebellion by the Romans. The expulsions of the Jews from England, France and Spain were assigned to this date, and it also commemorates various destructions of Jewish communities during the Middle Ages and pogroms. Most recently, the bombing of the AMIA (Jewish community building) in 1994 occurred the day after Tisha B’Av and is remembered on Tisha B’Av.
Are all these dates historically accurate? Probably not. But that’s not really why we set this one day aside for mourning. If we had separate days for mourning each tragedy, we’d be fasting 365 days a year. It was probably one of the wise acts of the rabbis – who were definitely not always wise – to set aside one day for mourning and allowing us the rest of the year to enjoy being Jewish.