The leftist Polish Socialist Party (Polska Partia Socjalistyczna, PPS) and the nationalistic National Democracy (Narodowa Demokracja) were the two most powerful Polish pro-independence groups established towards the end of the 19th century which continued their political activity in the 20th century. Among the most prominent figures in the first one was Józef Piłsudski (pseudonym “Ziuk”), a nobleman from the Vilnius Region leading the PPS Combat Organisation.
PPS itself was a heterogeneous environment, a characteristic proven by clashes between its members over its politics during the Revolution of 1905, which broke out in the Russian Empire and was aimed against the emperor’s rule after the Russian defeat in an ongoing war with Japan. The “young” part of PPS propagated Marxist principles, such as class struggle and revolution, and wanted to participate in the all-Russian socialist movement. In contrast, the “old” PPS members, including Piłsudski, were against such plans and considered themselves to be rather continuators of the Polish insurrectionist tradition, defending the struggle for the independence of Poland and provoking a nationwide military uprising. The friction led to a split inside PPS during the 9th party convention in Vienna in 1906 into the Polish Socialist Party – Left, embracing the “young” members, and the Polish Socialist Party – Revolutionary Faction, including Piłsudski and his collaborators. What is important is that the split was not a formal one and the two groups continued to exist within PPS.
In 1906–1907, Piłsudski decided that it was impossible to keep successfully fighting against Russia in the Kingdom of Poland and put the insurrection plans to work. In that situation, Ziuk focused on gathering financial resources for further activities and forming an organisational basis for military activities, including the establishment of the Association for Active Struggle (Związek Walki Czynnej) in 1908. Piłsudski’s letter to Perl shows the turn he took in the decisive moment for the Polish pro-independence left.
One of the first manifestations of the new politics described by Piłsudski in the letter took place on 2 September 1908, when the socialist revolutionaries assaulted a Russian mail train near Bezdany and stole more than 200,000 rubles. The resources were later transported to Galicia and used to settle the debts of PPS and support the families of their imprisoned companions.