20/26 Sivan 5408 (1648)
On 26 Sivan 5408, in the face of the rampaging Cossack army, the Jews of Alik, Ukraine, huddled in the town’s shul. Rabbi David HaLevi Segal — most well known for his commentary on the Shulchan Aruch, Turei Zahav (commonly abbreviated as Taz) — joined them, having taken refuge in Alik from his own hometown. According to a story in the Minhagei Beis Alik on Chabad.org, the Taz fell asleep and dreamed of a verse from Melachim II (19:34), in which Hashem promises to King Hezekiah, “‘And I will protect this city to save it, for My sake and for the sake of My servant David.’” Per the story, the cannons fortifying the city then miraculously turned around and fired at the invaders, causing the Cossacks to flee.
Unfortunately, other Jews in the region were often not so lucky. Led by the Cossak Bogdan Chmielnitzki, mobs rampaged around Ukraine during the years 1648-1649, rising in rebellion against their Polish rulers; at the same time, they killed tens of thousands — perhaps even hundreds of thousands — of Jews. Chmielnitzki is, to this day, viewed by Ukranians as a national forefather. The corresponding years, 5408-5409, are known as gezeiros tach v’tat, the decrees of the Hebrew acronyms for ת”ח and ת”ט, due to the tremendous loss of Jewish life.
Six days before the Taz’s miraculous salvation, the 20th of Sivan, marked one of the worst days during this period. The Shach records in his Megillah Eifah that members of surrounding villages took refuge in the relatively large town of Nemirov. Polish soldiers opened the gates to the city, and for the next three days, the Cossacks killed about 6,000 Jews in the city. In the following weeks and months, they killed many more in the countryside and surrounding areas.
However, the misfortunes of the Jewish people of Europe on 20 Sivan began centuries before. In Blois, France, a Christain servant accused a Jewish man of murdering a Christain boy, who historians believe was either killed by the accuser or never existed — a body of the child was never found. It was the first blood libel in European history, and on 20 Sivan 4931 (1171), the town’s Jewish community was burned at the stake after refusing to renounce Judaism. Rabbeinu Tam declared the day a fast day for the communities of Rhineland and compiled selichos prayers to be recited.
The corresponding years, 5408-5409, are known as gezeiros tach v’tat, the decrees of the Hebrew acronyms for ת”ח and ת”ט, due to the tremendous loss of Jewish life.
Five hundred years later, the Taz (Orach Chaim 566:3) and Magen Avraham (Orach Chaim 568:10 and 580:9) report that the rabbis of Poland and the surrounding areas declared a fast day on 20 Sivan to commemorate the events of Nemirov and the gezeiros tach v’tat. The Taz and Magen Avraham both lost their parents in the Chmielnitzki massacres.
Nowadays, the custom to fast on 20 Sivan seems to have mostly fallen by the wayside, and all martyrs of Jewish history are mainly remembered in the kinnos, or lamentations, recited the morning of Tisha B’Av.