How did the Sejm function in the Polish-Lithuanian Commonwealth?

In the Polish-Lithuanian Commonwealth, the Sejm functioned as the central legislative body, deeply influenced by the political ideals of the szlachta (gentry). Unlike the trend toward absolutism elsewhere in Europe, the Commonwealth operated under a szlachta democracy that prioritized the absolute equality of all noble members.12

A defining and ultimately destabilizing feature of the Sejm was the liberum veto. Based on the principle that all legislation required unanimous consent, this legal right allowed any single member to defeat a measure or dissolve the entire session, nullifying all acts passed during it. Proponents viewed this as a vital safeguard against tyranny and a protection of local interests, as deputies were bound by instructions from local sejmiki (regional assemblies).32

In practice, however, the liberum veto frequently paralyzed the government. It prevented the centralization of power and left the state vulnerable to foreign influence, as external powers often bribed deputies to adjourn sessions that threatened their interests. This political stagnation hindered necessary reforms in finance, administration, and the military, eventually contributing to the decline of the Commonwealth.312