The Polish-Lithuanian Commonwealth (or The Commonwealth of the Two Nations) was a federal monarchy-republic formed by the Kingdom of Poland and Grand Duchy of Lithuania, between 1569 and 1795, which was governed by an elected monarch.

Since the word Poland was also commonly used to described the whole country, the members of the commonwealth were called:

The Crown had approximaterly double the population of Lithuania and five times the income of its treasury.

In the Partitions_of_Poland in 1772-1795 divided the country between Russia, the Kingdom of Prussia and Austria. However, the last political movement that wanted to restore the state was active about the time of the January Uprising (1863-1864).

These lands are distributed today among Poland, Lithuania, Latvia, Estonia, Ukraine, Belarus, and partly Russia.

The term "Commonwealth" is a close translation of the Polish word "Rzeczpospolita", which derives from latin res publica, see "Poland".

The political doctrine of Polish-Lithuania was "our state is a Republic under the presidency of the King". The Commonwealth introduced the doctrine of religious tolerance, had its own parliament, the Sejm, and elected kings that were bound to the contracts "Pacta conventa" from the beginning of their reign.

The foundation stones of the Commonwealth, the so called Golden Freedoms, were commonly:

  • free election of the king
  • "pacta conventa" that were binding for the king
  • "rokosz" a legal rebellion of citizens against the king that violated the freedoms
  • "liberum veto" the right to express opposition to the decisions of the majority by an individual
  • "confederatio" the military organisation of the citizens willing to achieve a common political aim.

See also: The Noble Republic, List of Polish rulers