In 1638, Sweden was a world power. One of the ways it showed this was by planting a Swedish colony between the rival claims of the New Netherland colony on the Hudson River, and of England’s Lord Baltimore’s claim to Maryland on the Chesapeake Bay. The New Sweden colony in America was built on the Delaware River with settlements stretching between what is now Wilmington, Delaware and Philadelphia, Pennsylvania with a fort and few additional settlements on the New Jersey side of the river as well. Most of the 900 settlers were from Sweden but many Forest Finns,German craftsmen and mercenary soldiers also made their homes in the Swedish colony. The economic purpose of the colony was to grow tobacco and trap and trade for animal furs.
While showing the colors for Sweden it was only natural that the first Lutheran settlers and their ministers built the first Lutheran Church in America in New Sweden. The settlers of New Sweden also introduced Americans to the log cabin which became the most popular style of first home for American pioneers for the next 250 years.
International rivalry between Dutch, Swedish, and English colonies for the fur trade was deadly serious but could also be humorous.
"Stuyvesant, in the spring of 1648, sent an expedition to build a fort on the Schuylkill (River) further inland than any of the Swedish posts. This he called Fort Beversreede — 'beaver road' — for its purpose was to be the first point of contact with the Minqua (Indian) traders. But before the summer had passed, Printz built a Swedish fort, 'right in front of our Fort Beversreede,' wrote an indignant Dutchman. This building stood between the water's edge and the Dutch blockhouse, its back wall standing just twelve feet from the palisade gate of Fort Beversreede. The Indians thus found Swedes at the anchoring place and could not even see the Dutch post from the water." (Philip S. Klein, and Ari Hoogenboom, A History of Pennsylvania, 2nd ed. (University Park, Penn.: Penn State Press, 1980), 11. Digital copy by Google.)
In 1654 the New Sweden colony captured Fort Casimir from the New Netherland colony in what is now New Castle County, Delaware. The next year, the Dutch counter-attacked, conquered, and absorbed all of former New Sweden, but granted it some autonomy. In turn, the New Netherland colony was conquered and absorbed by the English nine years later in 1664.
For references to a list of some of the settlers in New Sweden, and citations describing forts, blockhouses, and other settlements in the colony see the FamilySearch Wiki article: New Sweden.