The Constitution of 3 May 1791 was adopted by the Great Sejm (parliament) of the Polish–Lithuanian Commonwealth. It was the first of its kind in Europe and the second in the world.
The Constitution of 3 May 1791 in Polish: Konstytucja 3 Maja, Lithuanian: Gegužės trečiosios konstitucija, was adopted by the Great Sejm (parliament) of the Polish–Lithuanian Commonwealth, a dual monarchy comprising the Crown of the Kingdom of Poland and the Grand Duchy of Lithuania.
Was drafted over 32 months beginning on 6 October 1788, and formally adopted as the Government Act (Ustawa rządowa), the legislation was designed to redress the Commonwealth's political defects.
The system of Golden Freedoms, also known as the "Nobles' Democracy," had conferred disproportionate rights on the nobility (szlachta) and over time had corrupted politics. The adoption of the Constitution was preceded by a period of agitation for and gradual introduction of reforms beginning with the Convocation Sejm of 1764 and the election of Stanisław August Poniatowski as the Commonwealth's last king.
3 May was declared a Polish holiday (Constitution Day—Święto Konstytucji 3 Maja) on 5 May 1791.
It was outlawed during World War II by both the Nazi and Soviet occupiers. It was celebrated in Polish cities in May 1945, although in a most spontaneous manner.
The 1946 anti-communist demonstrations did not endear it to the Polish communists, and it competed for attention with the communist-endorsed May 1 Labor Day celebrations in the Polish People's Republic; this led to its "rebranding" as Democratic Party Day and removal from the list of national holidays by 1951.
Until 1989, 3 May was a frequent occasion for anti-government and anti-communist protests. 3 May was restored as an official Polish holiday in April 1990 after the fall of communism.
In 2007, 3 May was declared a Lithuanian national holiday. Polish-American pride has been celebrated on the same date, for instance in Chicago, where since 1982 Poles have marked it with festivities and the annual Polish Constitution Day Parade.