c 1476 BCE- First of the "three days of preparation", in which people of Israel prepared themselves to receive the Torah. Moses taught Israel about the commandments of the preparation and how to prepare for receiving the Torah.
Moses returns Israel's reply to the LORD that they are willing to accept the Torah. (Exodus 19:8)
68 CE- In his advance towards the destruction of Jerusalem, Roman Emperor Titus Flavius Vespasianus ("Vespasian") captures Jericho and massacres all its inhabitants.
1096- Crusaders massacre the Jews of Mainz. The Mainz Jewish community was massacred during the First Crusades twice - on this date and 6 Sivan.
May 16, 1165- The Rambam (Maimonides) reaches the Land of Israel safely after fleeing from Spain and Morocco.
May 19, 1950- Operation Ezra and Nechemia brings Iraqi Jews to Israel.