11 November 1918 is considered the symbolic date on which Poland regained its independence. However, the process of laying down the legal foundations of the reborn state continued for a number of years. One of the main things was to draw up a constitution. As early as February 1919, the single-chamber Legislative Sejm (parliament) elected in January of that same year adopted the so-called Little Constitution which for the time being defined the basic operating principles of Poland’s state institutions.
Work on a new constitution continued. Its authors modelled it in part on the French constitutional laws of 1875. Efforts were made to ensure that the Basic Law provided a broad spectrum of civic liberties. It was also supposed to provide wide-ranging rights to the national and ethnic minorities living in the Republic of Poland.
The constitution was adopted on 17 March 1921, three days before the decisive Upper Silesia plebiscite whose outcome was to determine whether this important industrial region would go to Poland or Germany.
The adoption the March Constitution set in motion the process of electing the state authorities. In the autumn of 1922, elections to the Sejm and Senate (the upper chamber of parliament, established in line with the new constitution) took place. In December 1922, the National Assembly (both of the parliamentary chambers together) elected the first president of the Republic of Poland.
The 1921 constitution was amended in 1926. After Józef Piłsudski’s May Coup, the Sejm devalued the position of the legislative power in favour of the executive. The amended constitution remained in force until 1935, when it was substituted with a new Basic Law. In 1944, the Stalinist-imposed communist government rescinded the constitution of April 1935 and nominally recognised the March Constitution as binding, even though its democratic principles were not respected. This state of affairs was maintained until 1947.