Sejm of the Polish–Lithuanian Commonwealth
The General Sejm (Polish: sejm walny, Latin: comitia generalia) was the bicameral legislature of the Polish–Lithuanian Commonwealth. It was established by the Union of Lublin in 1569 following the merger of the legislatures of the two states, the Sejm of the Kingdom of Poland and the Sejm of the Grand Duchy of Lithuania.
Source: Wikipedia — Sejm of the Polish–Lithuanian Commonwealth (CC BY-SA 4.0)