Союз освобождения
In 1901, he was arrested and exiled again for participating in an anti-government demonstration. After his release, he lived in Finland, where he was involved in founding the Union of Liberation in 1903 with former Marxists P.B. Struve, S.N. Prokopovich and others. This became the nucleus of the Constitutional-Democratic Party; (Ka-Dets), tsarist Russia's main liberal party. However, Annensky also retained his connections with "narodnik" socialism and became involved in the Socialist-Revolutionary Party (PSR). He argued strenuously against the PSR's revival of political terrorism as a tactic and deplored the influence of Marxism on its leading theorists, such as V.M. Chernov.