Officers Rise for a Constitution in the Decembrist Revolt

On 14 December 1825 Old Style (26 December New Style), liberal army officers marched approximately three thousand troops into Senate Square in Saint Petersburg, seeking to force a constitutional transformation of the Russian Empire. The unexpected death of Emperor Alexander I weeks earlier had triggered a dynastic crisis. Alexander had no surviving legitimate children, and his elder brother Grand Duke Konstantin had privately renounced his right of succession years before. Because Konstantin's decision was kept hidden from the public and the armed forces, regimental guards initially swore allegiance to him. When the imperial court announced that his younger brother would instead take the crown as Nicholas I, conspirators seized the confusion of a rescheduled oath of allegiance to challenge the autocracy directly.

The conspiracy drew from underground reform societies established by officers following the Napoleonic Wars. Disturbed by the persistence of peasant servitude and encouraged by early imperial gestures toward reform, nobles had formed clandestine groups such as the Union of Salvation and the Union of Prosperity. By the early 1820s, the movement divided into two primary factions. The Northern Society, based in Saint Petersburg, favored a British-style constitutional monarchy, civil equality, and an end to serfdom that preserved aristocratic landholdings. In Ukraine, the Southern Society, led by Pavel Pestel, pursued a more radical path, proposing a republic, the execution or removal of the royal house, and the redistribution of landed estates to the peasantry.