Assassination of Gedaliah (423 BCE)
Tishrei 3rd is a fast day mourning the assassination of the Jewish royal Gedaliah ben Achikam, governor of the Land of Israel for a short period following the destruction of the First Temple. Gedaliah's killing spelled the end of the small remnant of a Jewish community that remained in the Holy Land after the destruction, which fled to Egypt. (According to many opinions, the assassination of Gedaliah actually occurred on Rosh Hashanah, but the commemoration of the event is postponed to the day after the festival).
Laws and Customs: Mourning the killing of Gedaliah (see "Today in Jewish History"), we abstain from food and drink from dawn to nightfall; selichot prayers are included in the morning prayer.