Intro to the article, "Tach V’Tat":
"The years 1648 and 1649 represent a watershed in Jewish history. In Jewish tradition they are referred to as “Tach V’tat” (which are the Hebrew letters representing the numbers 408 and 409, which correspond to the years 1648 and 1649 on the non-Jewish calendar). One can even say that Tach V’tat marks the beginning of modern Jewish history. It is certainly the harbinger of enormous changes in and enormous destruction of the Jewish world."
This is an example of Nationalism, as typically a charismatic leader rises up, as in this case, it was Bogdan Chmielnicki. As a solider of fortune, he was highly loyal to the Russian Orthodox Church. This passion fueled this massacre of many Jews and Polish Roman Catholics,
Human Nature has not changed.