Sweden's ambitious foreign policy brings it into conflict beginning in the mid-sixteenth century with the three other main powers that have an interest in the Baltic: Denmark, Poland, and Russia.

These three powers fight numerous wars with Sweden, which is at war for more than eighty of the last three hundred years it ruled Finland.

Finland itself is often the scene of military campaigns that are generally conducted as total war and thus include the devastation of the countryside and the killing of civilians.

One example of such campaigns is the war between Sweden and Russia that lasts from 1570 to 1595 and is known in Finland as the Long Wrath, because of the devastations inflicted on the country.

Sweden is also heavily involved in the Thirty Years' War (1618-48), in which the Swedes under King Gustavus II Adolphus thwarts the advance of the Habsburg Empire to the shores of the Baltic and thereby secure the Swedish possessions there.

Finnish troops are conscripted in great numbers into the Swedish army to fight in this or in other wars, and the Finns often distinguish  themselves on the battlefield.

Both Charles X of Sweden and Frederick William, Elector of Brandenburg, agree to establish an alliance against Poland under the terms of the Treaty of Königsberg, signed in Königsberg (Królewiec) on January 17, 1656.

Charles is responsible for forcing the prince-elector to become his ally and vassal.

Alexis of Russia declares war on Sweden in May 1656, taking advantage of Charles being bound in Poland, and Livonia, Estonia and Ingria being secured only by a Livonian army of twenty-two hundred  infantry and four huindred dragoons, Magnus de la Gardie's seven thousand men in Prussia, and six thousand nine hundred and thirty-three men dispersed in garrisons along the eastern Baltic coast.

A reserve force of the Russian army strikes across Swedish Ingria in July and overruns two key Baltic fortresses—Nöteborg and ...

...Nyen.

A Dutch garrison reinforces Danzig in late July and a combined Danish and Dutch fleet breaks the naval blockage imposed on the city by Charles.

A combined Brandenburgian-Swedish army is on July 28-30 able to defeat the Polish-Lithuanian army in the Battle of Warsaw, forcing John II Casimir to retreat to Lublin.

The main Russian forces, some thirty-five thousand strong, march along the bank of the Western Dvina towards Riga, along their way taking Daugavpils and ...

...Livonian Kokenhausen (Koknese).

A separate Russian detachment advances on Dorpat (Tartu) and ...