Combat Organization of the Polish Socialist Party
The Combat Organization of the Polish Socialist Party (Polish: Organizacja Bojowa Polskiej Partii Socjalistycznej, abbreviated OBPPS) was a Polish guerrilla resistance movement established in 1904 by Józef Piłsudski. It functioned as the paramilitary wing of the Polish Socialist Party.
The organization was most active between 1904 and 1908, growing to over 2,000 members, including more than 700 paramilitary fighters, and carrying out over 2,500 operations. At its peak, it boasted a membership of more than 5,000. Its primary objective was to mount an armed resistance movement against Imperial Russian rule in partitioned Poland. The group gradually declined and was dissolved in 1911.
Among its most notable actions were the Bloody Wednesday of 15 August 1906; the failed assassination attempt on Warsaw’s Governor-General, Georgi Skalon, on 18 August 1906; and the Bezdany raid, a large-scale train robbery on 26 September 1908.