Decembrists (dĬsĕm´brĬsts), in Russian history, members of secret revolutionary societies whose activities led to the uprising of Dec., 1825, against Czar Nicholas I. Formed after the Napoleonic Wars, the groups comprised officers who had served in Europe and had been influenced by Western liberal ideals. They advocated the establishment of representative democracy but disagreed on the form it should take; some favored a constitutional monarchy, while others supported a democratic republic. Their poorly organized rebellion was precipitated by the confusion surrounding the succession to the throne on the death of Alexander I. The more moderate members persuaded several regiments in St. Petersburg to refuse their oath of allegiance to the unpopular Nicholas and to demand that his elder brother, Constantine, who had secretly renounced the throne in 1822, be made czar and grant a constitution. The rebels marched to Senate Square and were crushed by artillery fire. Five of their leaders were later executed. The Decembrists' insurrection made a profound impression on Russia. It led both to the increasing police terrorism of the czarist government and to the spread of revolutionary activity among the educated classes.