Peter Stuyvesant, his successor, arrived at Fort Amsterdam in May 1647.
Friction had soon arisen with New Netherland, although, owing to their common dislike of the English, the Swedes and the Dutch had maintained a formal friendship. In 1651, however, Peter Stuyvesant, governor of New Netherland, and more aggressive than his predecessors, built Fort Casimir, near what is now New Castle.
In retaliation, Stuyvesant, in 1655, with seven vessels and as many hundred men, recaptured the fort and also captured Fort Christina (Wilmington).
Stuyvesant was, however, extremely arbitrary.
Stuyvesant conducted a successful expedition against the Swedes on the southern border of New Netherland in 1655; but he was powerless against the English.