Lublin, Union of 1569

an agreement to unite Poland and the Grand Duchy of Lithuania into one state, called the Polish-Lithuanian Commonwealth. Deliberations for the conclusion of the union began in January 1569 in Lublin at a joint sejm of the Polish and Lithuanian feudal lords. The agreement was signed on June 28, and on July 1 it was confirmed separately by the deputies of the Polish and Lithuanian sejms. The Lublin union completed the unification of the two states that had begun with the Krewo Union of 1385.

The union provided for the establishment of a uniform political system, a common currency, and a joint sejm for Poland and Lithuania. The commonwealth was to be headed by a king elected jointly by the Polish and Lithuanian feudal lords. The union confirmed the incorporation of part of the Grand Duchy of Lithuania into the kingdom of Poland, declared Livonia to be the joint possession of Poland and Lithuania, and abolished customs barriers between the two countries. The commonwealth was to function as a single state in international affairs. The Union of Lublin, however, did not entirely abolish Lithuania’s autonomy, for the grand duchy retained its legislature and courts, some high administrative posts, its treasury, and its army. Byelorussian continued to be the official language of Lithuania. These elements of statehood disappeared in the course of the 17th and 18th centuries. The Constitution of May 3, 1791, abolished the vestiges of Lithuanian autonomy.