The events of the year 1920 were a unique breakthrough in Polish history, yet now are largely forgotten. The war between the Republic of Poland and the Russian Bolsheviks was, after all, a threat to all of Europe. In Białystok the rulers of red Russia organized their own administration known as the Polish Provisional Revolutionary Committee to govern conquered parts of Polish territory. This body was ultimately going to have transformed itself into the government of a Polish Soviet Republic. This process, as well as the building of the Polish Red Army, is described in the reviewed book. Dr. Klimecki’s work also recounts the social background of Polish collaborators of Polish and Jewish origin from soldiers of the Red Army to Polish members of the Communist Party. Fortunately, Polish forces stopped the Bolsheviks at the battle of Warsaw, after which Poland enjoyed twenty years of independence. The reviewed book is an exceptional example of diligent academic work which also describes a now halfforgotten event in the war of 1920.