Oisin Allen

Second Northern War
Part of Northern Wars
March across the Belts
Date 1655–1660 Location Denmark, Sweden, Polish–Lithuanian Commonwealth, Eastern Seaboard Result Treaties of Roskilde (1658) and Copenhagen (1660) (Sweden and Denmark) Treaty of Oliva (Sweden and Habsburg, Brandenburg, Poland–Lithuania) Treaties of Valiesar (1658) and Cardis (1661) (Sweden and Russia) Territorial changes Scania, Halland, Blekinge, Bohuslän and Ven become Swedish Duchy of Prussia becomes a sovereign state Sweden's sovereignty in Swedish Livonia accepted New Sweden seized by New Netherland
Belligerents
Sweden Brandenburg-Prussia Transylvania Ukrainian Cossacks (1657) Grand Duchy of Lithuania Wallachia Moldavia Susquehannock	Poland–Lithuania Denmark–Norway Habsburg Monarchy Russia (1656–58) Crimean Khanate Brandenburg-Prussia Dutch Republic
Commanders and leaders
Charles X Gustav Arvid Wittenberg Magnus de la Gardie Carl Gustaf Wrangel Gustaf Otto Stenbock Per Brahe the Younger Johan Risingh Frederick William I George II Rákóczi Col. Anton Zhdanovich	John II Casimir Vasa Stefan Czarniecki Janusz Radziwiłł Paweł Jan Sapieha Stanisław Lanckoroński Stanisław Potocki Wincenty Gosiewski Frederick III Ulrik Frederik Gyldenløve Anders Bille † Iver Krabbe Alexis of Russia Matvey Sheremetev † Frederick William I Raimondo Montecuccoli Jean-Louis Raduit de Souches Peter Stuyvesant
Casualties and losses
70,000 Swedish dead (mercenaries not included)

Colonial Actions

Potential addition to the Second Northern War article.

In the early 17th Century, both Sweden and the Dutch Republic had established colonies in eastern North America: New Sweden and New Netherland, respectively. These colonies had a long-standing dispute over the land around the Delaware River, which had first been claimed by the Dutch, but was occupied almost exclusively by the Swedish. In 1654, at the peak of this dispute, Swedish Governor Johan Risingh seized the Dutch Fort Casimir, which was renamed Fort Trinity. Upon the outbreak of the Second Northern War, Dutch Director-General Peter Stuyvesant took the opportunity to strike back at New Sweden, and launched an assault on the colony on September 11, 1655. Fort Casimir was recaptured, and by September 15, an armed squadron of Dutch ships had fully occupied the Swedish colony.

This marked the end of Swedish colonization of continental North America, much to the chagrin of the Susquehannock, a highly influential Native American nation who were one of the greatest powers on the Eastern Seaboard at the time. The Susquehannock were close allies of the Swedish colonists, and treated New Sweden as something of a protectorate. In response to the Dutch removal of their main European trading partner, they launched a series of attacks on Dutch settlements in modern-day Manhattan, Staten Island, Yonkers, Jersey City and the Bronx on September 15, while Stuyvesant and most of the Dutch colonial military were still in New Sweden. These attacks devastated the Dutch, who withdrew into New Amsterdam, abandoning many of their outlying settlements.