The Russian Revolution of 1905, also known as the First Russian Revolution, occurred on 22 January 1905, and was a wave of mass political and social unrest that spread through vast areas of the Russian Empire. The mass unrest was directed against the Tsar, nobility, and ruling class. It included worker strikes, peasant unrest, and military mutinies.

The 1905 revolution was primarily spurred by the international humiliation as a result of the Russian defeat in the Russo-Japanese War, which ended in the same year. Calls for revolution were intensified by the growing realisation by a variety of sectors of society of the need for reform. Politicians such as Sergei Witte had succeeded in partially industrializing Russia but failed to reform and modernize Russia socially.

Calls for radicalism were present in the 1905 Revolution, but many of the revolutionaries who were in a position to lead were either in exile or in prison while it took place. The events in 1905 demonstrated the precarious position in which the Tsar found himself. As a result, Tsarist Russia did not undergo sufficient reform, which had a direct impact on the radical politics brewing in the Russian Empire. Although the radicals were still in the minority of the populace, their momentum was growing. Vladimir Lenin, a revolutionary himself, would later say that the Revolution of 1905 was "The Great Dress Rehearsal", without which the "victory of the October Revolution in 1917 would have been impossible".