In the world of the seventeenth century, the first requirement of a military or trading outpost was a fort. The fort was the center of trading activity, but, of course, its main function was military. Once Manhattan Island was chosen as the center of the New Netherland colony, the choice of location for the fort was obvious. It would be, as Adriaen Van der Donck wrote in 1649, twenty-five years after it was built, "in the south point of Manhattan island, at the junction of the East and North rivers." The purpose was "not only to close and command the said rivers" but "to possess as well all the lands comprehended between them as round about them..."
Maintaining the fort was to remain an issue throughout the life of the colony. In 1643, a visiting Jesuit priest noted that the fort had four bastions and several cannon. The walls, however, were "but mounds, most of which had crumbled away, so that one entered the fort on all sides." Van der Donck, a critic of the West India Company administration, similarly noted that the fort "lies like a molehill or a tottering wall," and reported that the cannons were not mounted on proper platforms. In answer to these charges, Cornelis Van Tienhoven, Petrus Stuyvesant's secretary and mouthpiece, snipped, "That the fort is not properly repaired does not concern the inhabitants. It is not their domain, but the Company's."
Despite its sorry condition, the fort remained the center of the colony. It was here that the director held his council sessions. For many years the directors lived within the fort. And of course the West India Company soldiers were garrisoned here. During Indian assaults, the residents of the town ran within the walls for safety. In 1664, from his position on the ramparts of the fort, Petrus Stuyvesant studied the advance of English soldiers and sailors, before finally agreeing to surrender his colony. At once, the new English commander, Richard Nicholls, renamed it Fort James (after the Duke of York, for whom, of course, the city and colony were renamed as well).
Most notably for the sake of later history, it was in the fort that the secretary of the Dutch colony had his office and kept the record books. When English troops took over, the English secretary likewise kept his office in the fort. And so, humble though it was, we owe to Fort Amsterdam the survival of the records of this vital period in American history. The same records that sat for decades in the secretary's office are now housed in a vault at the New York State Library in Albany. It is these that Charles Gehring, the director of the New Netherland Research Center, has translated and published since 1974, giving scholars, and the rest of us, access to hearts, minds and concerns of the men and women of New Netherland.
The site of Fort Amsterdam is now occupied by the old U.S. Custom House building, which houses the Smithsonian Institution's Museum of the American Indian.
Seventeenth-century Dutch forts followed a similar design wherever they were built. Here is a website devoted to Dutch forts in Ghana.
Fort Amsterdam was a West India Company outpost, founded originally to help the company fight the war against Spain. Here is an English translation of the original 1621 charter of the West India Company.