Kardis, Treaty of 1661

a treaty concluded between Russia and Sweden on June 21 (July 1) in the village of Kardis, near Derpt (Tartu); it ended the Russo-Swedish War of 1656–58 with an “everlasting peace.”

The Swedish delegation was headed by Bengt Horn; the Russian, by Prince I. S. Prozorovskii. Russian military defeats from 1659 to 1662 in the Russian-Polish War of 1654–67 and the conclusion of the Peace of Oliva of 1660 between Poland and Sweden created conditions unfavorable for Russia. Tsar Aleksei Mikhailovich rejected A. L. Ordin-Nashchokin’s proposal to abandon claims to the Ukraine in order to conclude peace with Poland and thus have the means to continue war against Sweden over Livonia. As it was unable to continue to fight simultaneously against both Sweden and Poland, the Russian government was forced to conclude the Kardis Treaty and to return to Sweden the Estonian and Livonian cities ceded to Russia in the Valiesar Truce of 1658. The border specified in the Peace of Stolbovo of 1617 was restored. The Kardis Treaty made possible the continuation of the Russian war effort against Poland for the Ukraine and Byelorussia because Sweden was obliged not to assist Poland.