Articles of the Warsaw Confederation are signed, sanctioning freedom of religion in Poland.
The Warsaw Confederation, signed on 28 January 1573 by the Polish national assembly (sejm konwokacyjny) in Warsaw, was one of the first European acts granting religious freedoms. It was an important development in the history of Poland and of Lithuania that extended religious tolerance to nobility and free persons within the Polish–Lithuanian Commonwealth and is considered the formal beginning of religious freedom in the Polish-Lithuanian Commonwealth. Although it did not prevent all conflict based on religion, it did make the Commonwealth a much safer and more tolerant place than most of contemporaneous Europe, especially during the subsequent Thirty Years' War.