On July 1, 1569 at the General Sejm in Lublin the Act of Union of the Grand Duchy of Lithuania and the Kingdom of Poland was signed. The resulting Polish-Lithuanian Commonwealth became one of the most powerful political entities in Europe at that time. On the 450th anniversary of this event, the Members of Parliament, during their 82nd sitting, adopted a special resolution by acclamation. They stressed that the Polish-Lithuanian Union enabled the birth of a unique system of statehood and was one of the most important events of the century on the continent.

"The act of concluding the union was proof not only of the practical implementation of the ideas of the Renaissance era, but also of innovative legal thought and a testimony to the political maturity of the political elites of both states," the resolution wrote.

The Sejm emphasized in the document that the act of the Union of Lublin brought into being "a multinational and multireligious community, built on republican values, on the idea of tolerance, political negotiation and mutual respect", while "the Polish-Lithuanian Commonwealth became a bridge between East and West, a refuge of democracy and a true Antemurale Christianitatis".

The deputies also expressed their hope that the traditions of shaping political identity and parliamentary culture of the citizens of the former Polish-Lithuanian Commonwealth will take their rightful place in the history of parliamentarism in Lithuania and Poland.

In a special message prepared for the 450th anniversary of the Union of Lublin, the President of the Seimas of the Republic of Lithuania, Viktoras Pranckietis, stressed that this act is a testimony of a unique political agreement between two states. - The Union's solutions, based on the multicultural and multinational tradition of the Jagiellonian monarchy, were innovative and built one of the most powerful states on the continent. The 450th anniversary of the Union of Lublin is an excellent testimony of our unity," said the Speaker of the Lithuanian Parliament in a recording presented in the Plenary Hall.