formation of new Jewish Communist Defense League in Russian

Organized attacks on Jews have historically been called POGROMS. Pogroms differ from events like the Holocaust in that pogroms were (1) not well-planned or well-coordinated and (2) localized in particular villages or cities. Most pogroms in Jewish history took place in the Russian Empire and its subsequent governments, but there have been pogroms in nearly every Old-World country that has hosted Jews other than India.

Pogroms were violent riots and massacres launched against Jews and frequently encouraged by government authorities.

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It was, above all, Tsarist Russia that was associated with pogroms. In Russia the whole period from about 1881-1917 was charcterized by pogroms.

Nazi Germany staged the Night of the Broken Glass, but on the whole preferred to avoid public disturbances when implementing its anti-Jewish policies.

In 1941 there were pogroms in Romania, especially Bucharest and Iasi, with Jews being beaten up and killed in the street.

One of the best know pogroms was that at Kishinev in 1903. See the link.

See also the second link, which has a map of some of the places where pogroms occurred in the Russian Empire.

It is unclear what this question is asking.

If it is asking what a pogrom was as an event, it was a series of quasi-coordinated attacks by armed Russian civilians and Cossacks on civilian Jewish populations purely because of Anti-Semitic motives.

If it is asking what the names were of the various Russian pogroms, please see the Related Links which discuss various pogroms across the world. There were over hundreds of distinct pogroms. Among the worst were the Odessa Massacres, the Kiev Pogroms, the Warsaw Pogroms, the Kishinev Pogroms, and numerous others.

The Russian government