New Sweden, or Nya Sverige, was a Swedish colony in North America corresponding roughly to today's state of Delaware but also containing settlements in New Jersey, Pennsylvania, and Maryland. The colony existed from March 29, 1638 to September 1655.
By the middle of the 17th century the Realm of Sweden had reached its greatest territorial extent and was on the verge of becoming one of the great powers of Europe. Sweden then included Finland along with parts of modern Russia, Poland, Germany, Estonia, and Latvia. They sought to extend their influence by creating an agricultural (tobacco) and fur trading colony to bypass French and British merchants. The New Sweden Company was chartered and included Swedish, Dutch and German stockholders.
The first Swedish expedition to North America was launched in late 1637. Samuel Blommaert assisted with the fitting-out and appointed Peter Minuit to lead the expedition. Minuit was formerly the governor of the Dutch colony of New Netherland. The expedition arrived in Delaware Bay, a location within the territory claimed by the Dutch, in late March 1638. They built a fort on the present-day location of the city of Wilmington which they named Fort Christina, after Queen Christina of Sweden. In the following years, some 600 Swedes and Finns settled in the area.
In May 1654, the Dutch Fort Casimir was conquered by the New Sweden colony, led by governor Johan Rising. The fort was taken without force since no gunpowder was present, and the settlement was renamed Fort Trinity. As reprisal, the Dutch - led by governor Peter Stuyvesant - moved an army to the Delaware River in the late summer of 1655, leading to the immediate surrender of Fort Trinity and Fort Christina.
The Swedish and Finnish settlers continued to enjoy a degree of local autonomy, having the right to their own militia, religion, court, and lands. This status lasted officially until the English conquest of the New Netherlands colony, in October 1664, and continued unofficially until the area was included in William Penn's charter for Pennsylvania, in 1682. During this later period some immigration and expansion continued. The first settlement and Fort Wicaco were built on the present site of Philadelphia in 1669.