<a href="https://en.wikipedia.org/wiki/Second_Northern_War" id="mwLQ" rel="mw:WikiLink" title="Second Northern War">Second Northern War</a>: <a href="https://en.wikipedia.org/wiki/Battle_of_Warsaw_(1656)" id="mwLg" rel="mw:WikiLink" title="Battle of Warsaw (1656)">Battle of Warsaw</a> begins.