Union of Lublin
The Union of Lublin (; ) created the single state of the Polish–Lithuanian Commonwealth on July 1, 1569 with a real union between the Crown and the Grand Duchy of Lithuania. Before then, the Crown of the Kingdom of Poland and the Grand Duchy of Lithuania only had a personal union. The Union of Lublin also made the Crown an elective monarchy; this ended the Jagiellonian dynasty once Henry de Valois was elected on May 16, 1573 as monarch.