Editors. "Ivan IV of Russia gains Polotski from Poland". The Literary Encyclopedia. First published 01 February 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=15019, accessed 24 May 2013.]
Ivan IV of Russia conquers Polotski in Eastern Livonia, which was part of Poland. As a result of this, intermittent warfare between the two countries continues to 1582.