Why was the May 3 Constitution proclaimed in Warsaw in 1791?

The May 3 Constitution was proclaimed in Warsaw in 1791 as a desperate, revolutionary effort to modernize the Polish-Lithuanian Commonwealth and preserve its sovereignty against the threat of further partitions by neighboring powers.123

During the "Great Sejm" (1788–1792), reformers sought to dismantle the nation's "anarchical" political system, which had been paralyzed by the liberum veto and obstructive class distinctions. By 1791, the international climate—including a Russo-Turkish war and the French Revolution—provided a window of opportunity for reform.124

To ensure its passage, reformers utilized an "audacious surprise" during the Easter recess, when many opposition members were absent. King Stanisław II August Poniatowski urged the Sejm to adopt the document as the final means of saving the country from collapse. The resulting constitution established a constitutional parliamentary monarchy, abolished the liberum veto, and introduced Enlightenment-inspired reforms to strengthen the state's military and administrative capacity.214