Between 1918 and 1921, a wave of mass violence swept through the Jewish communities of Ukraine that the world has largely forgotten. In 1,500 pogroms across more than 1,300 localities, somewhere between 50,000 and 200,000 Jews were killed — not as a by-product of revolution but as its recurring, systematic accompaniment. Every armed force fighting in the Ukrainian Civil War bore some responsibility: the Ukrainian Directory under Symon Petliura, whose forces committed the largest single share of the documented violence; the White Army under Denikin, whose Cossack cavalry brought the Judeo-Bolshevik myth to lethal operational form; the independent warlord bands who turned the chaos of the steppe into a hunting ground; and even, in limited instances, units of the Bolshevik Red Army.Drawing on the extraordinary archive assembled by historian Elias Tcherikower — thousands of survivor testimonies, administrative records, and photographs preserved at the YIVO Institute — Conrad Brennan reconstructs the full scope of a catastrophe that has lived in the shadow of the Holocaust it helped to make possible. From the organised massacre at Proskurov to the burning synagogue at Tetiev, from the ideology of Judeo-Bolshevism to the failure of international accountability, this is the definitive narrative history of a forgotten genocide — and a reckoning with what it cost the world to forget it.