Treaty of Vilnius (1561)

The Treaty of Vilnius or Vilna was concluded on 28 November 1561, during the Livonian War, between the Livonian Confederation and the Grand Duchy of Lithuania in Vilnius. With the treaty, the non-Danish and non-Swedish part of Livonia, with the exception of the Free imperial city of Riga, subjected itself to the Grand Duke of Lithuania, Sigismund II Augustus with the Pacta subiectionis (Provisio ducalis). In turn, Sigismund granted protection from the Tsardom of Russia and confirmed the Livonian estates' traditional privileges, laid out in the Privilegium Sigismundi Augusti. The secularization of the Livonian Order was the "final act" in Livonia's transition from the Middle Ages to the Early Modern era. The territories were re-organized in the Duchy of Courland and Semigallia and the Duchy of Livonia, the latter competing with the Kingdom of Livonia during the war. After its reconquest, Sigismund's successor Stephen Báthory (Batory) ignored the privileges of 1561, granted a new constitution and initiated counter-reformation. These measures were reversed after the Swedish conquest. When after a further series of wars Livonia capitulated to Russia in 1710, the Privilegium Sigismundi Augusti was confirmed by Peter the Great. In 1513, the Grand Master of the Livonian Order bought his order out of the union with the Teutonic Knights. Thus, the secularization of the Teutonic Order State, which led to the establishment of the Protestant Duchy of Prussia under the Polish king in 1525, did not affect Livonia, where the Recess of Wolmar (Valmiera) forbade any future secularization in 1546. The Protestant Reformation had started in Riga in 1517, and afterward it had spread to all of Livonia; religious freedom was declared in 1554. As the Livonian Confederation was in decline due to internal struggles, a faction of the order favored rapprochement with Poland–Lithuania, while another faction violently opposed it. After a civil war starting in 1556, the pro-Polish faction gained the upper hand.