Occupation of Poland-Lithuania and the Brandenburgian intervention

Meanwhile, Russian and Cossack forces had occupied the east of the Polish–Lithuanian Commonwealth as far as Lublin, with only Lwow (Lviv, Lemberg) remaining under Polish–Lithuanian control. In late October, Charles X Gustav headed northwards and left Wittenberg in Kraków with a mobile force of 3,000 Swedish and 2,000 Polish troops, and an additional number scattered in garrisons, to control the southern part of the Swedish-occupied commonwealth.

Approximate extent of Swedish-occupied (light blue) and Russian-occupied (light green) Poland-Lithuania

In the north, the Royal Prussian nobles concluded a defensive alliance with the Electorate of Brandenburg on 12 November in the Treaty of Rinsk, permitting Brandenburgian garrisons. Danzig (Gdansk), Thorn (Torun) and Elbing (Elblag) had not participated in the treaty, with Thorn and Elbing surrendering to Sweden. In the Treaty of Königsberg on 17 January 1656, Frederick William, Elector of Brandenburg and Duke of Prussia, took the Duchy of Prussia, formerly a Polish fief, as a fief from Charles X Gustav. The Brandenburgian garrisons in Royal Prussia were withdrawn, and when Marienburg (Malbork) surrendered in March, Danzig remained the only town not under Swedish control.

The rapid Swedish invasion and occupation of the Polish–Lithuanian territories became known in Poland as the "(Swedish) deluge."

• Outline of the Second Northern War (1655–1660)
  

  HISTORIC BATTLES

  Second Northern War (1655–1660)

  The Second Northern War (also First or Little Northern War) was fought between Sweden and its adversaries the Polish–Lithuanian Commonwealth, Russia, Brandenburg-Prussia, the Habsburg Monarchy and Denmark–Norway. The Dutch Republic often intervened against Sweden. View Historic Battle »

  Prelude: Sweden, at that time an expansionist empire with an army designed to be maintained by the revenues of occupied territory, was conscious that a direct attack on her main adversary Russia could well result in a Dano-Polish–Russian alliance.

  Swedish campaigns in the Polish–Lithuanian Commonwealth: On the western front, Wittenberg was opposed by a Polish levy of 13,000 and an additional 1,400 peasant infantry.

  Occupation of Poland-Lithuania and the Brandenburgian intervention: In the north, the Royal Prussian nobles concluded a defensive alliance with the Electorate of Brandenburg on 12 November in the Treaty of Rinsk, permitting Brandenburgian garrisons.

  Polish–Lithuanian recovery: Charles X Gustav, with a force of 11,000 horse, reacted by pursuing Czarniecki's force of 2,400 men, confronting and defeating him in the Battle of Gołąb in February 1656.

  Brandenburgian-Swedish alliance and Russia's war on Sweden: On 25 June 1656, Charles X Gustav signed an alliance with Brandenburg: the Treaty of Marienburg granted Greater Poland to Frederick William in return for military aid.

  Swedish–Brandenburgian–Transylvanian–Romanian alliance and the truces with Russia: Rákóczi entered the war in January 1657, crossing into the commonwealth with a force of 25,000 Transylvanian-Wallachian-Moldavian men and 20,000 Cossacks who broke the Polish siege of Kraków before they met with Charles X Gustav, who had led a Swedish-Brandenburgian army southwards.

  Austro–Brandenburgian–Polish alliance, Danish campaigns in Sweden: On 1 December 1656, he signed an alliance with Ferdinand III of Habsburg in Vienna, essentially a declaration of Ferdinand III's intend to mediate a peace rather than provide military aid, which did not come into effect until Ferdinand's death on 2 April 1657.

  Denmark and Pomerania: The attack of Frederick III of Denmark in June 1657, aimed at regaining the territories lost in 1645, provided an opportunity for Charles X Gustav to abandon the unfortunate Polish–Lithuanian battlefields.

  Sweden entrenched: In 1659, the war was characterized by Swedish forces defending their strongholds on the southern Baltic coast against allied assaults.

  New Sweden: The Dutch moved an army to the Delaware River in the summer of 1655, easily capturing Fort Trinity and Fort Christina.

  Peace: Russia, still engaged in the Russo-Polish War (1654–67), settled her dispute with Sweden in the Treaty of Kardis, which restored Russian-occupied Swedish territory to Sweden.

RESOURCES
This article uses material from the Wikipedia article "Second Northern War", which is released under the Creative Commons Attribution-Share-Alike License 3.0.