200th anniversary of the introduction of the four-year Sejm (1788-1792).
Stanisław Małachowski and Kazimierz Nestor Sapieha,
Marshals of the Sejm
(a painting by Józef Peszka)
With Russia busy at war, the Reformists convened a Sejm (Diet or Parliament) in Warsaw in 1788 that lasted four years.
The first written constitution in the world was the United State's, ratified in 1789 just two years prior to the that of Poland-Lithuania's. Poland-Lithuania was heavily influenced by the changes going on in America and thus wrote theirs. The third written constitution in the world was France's in 1795 following the French Revolution, another event highly-influenced by the American bid for independence.
Sejm Cztero-letni 1788-1792 = The Four-Year Sejm (or the Great Sejm) 1788-1792.
Kazimierz Nestor Sapieha
Polish Constitution of May 3, 1791
Józef Peszka (artyzm.com)