Tisha B'Av History
Tisha B'Av, the ninth of Av, is a full day of fasting and mourning. The month of Av usually falls in the height of the summer. Even with regard to climate, it was the driest time of the year, and thus a time of sadness and uncertainty until the rains came again.
Although the festival commemorates the destruction of both Temples, the main historical sources are in dispute about exactly when the Temples were destroyed. Some say the first Temple was destroyed either on the seventh or the 10th of Av in 586 B.C.E. by Nebuchadnezzar (king of Babylonia), and the second Temple was destroyed on the 10th (70 C.E. by Titus).
The rabbinic authorities decided to mark the ninth as the official date of remembering their destruction.
Tisha B'Av is the saddest day in the Jewish calendar, and over the centuries many tragic events happened--or were traditionally said to have happened--on this date. These include the capture of Bethar, which marked the final defeat of Bar Kokhba's rebellion against the Romans, and the razing of Jerusalem by the Romans. The edict of King Edward I compelling the Jews of England to leave the country was signed on the ninth of Av in 1290, the Jews were expelled from Spain on that day in 1492, and World War I broke out in 1914. The sadness and mourning that Jews feel on this day are reflected in the various practices of Tisha B'Av, including abstaining from joyous activities like study of Torah, from eating and drinking, from sexual activity, and from wearing leather.