In April 1624, Nicolaes van Wassenaer reported: “They also placed a fort which they named ‘Wilhelmus’ on Prince’s Island, heretofore called Murderer’s Island; it is open in front, and has a curtain in the rear and is garrisoned by sixteen men for the defence of the river below.” Although the two islands mentioned by Van Wassenaer do not occur on early maps, an anonymous map of ca. 1630 provides the name “Willems Rivier” for the upper reaches of the Delaware. On this basis, C.A. Weslager presumed that Fort Wilhelmus was located on this river, even though Van Wassenaer’s information is immediately preceded by a reference to the building Fort Orange on the Hudson River. Other sources indicate that the Walloon families arriving in New Netherland in 1624 were spread out over four locations, one of which is named as “the High Island, situated about 25 miles up the South River, below the first falls.” This island (identified as Burlington Island) is considered to be the location of Fort Wilhelmus, which was intended to be the main headquarters of New Netherland. For about two years, a fortification served to protect a small group of colonists, consisting of two families and eight men, before the settlers were moved to Manhattan in 1626 in order to better withstand a feared attack by Native Americans. An additional argument in favor of abandoning Fort Wilhelmus was that the Delaware River froze solid during the winter, leaving the outpost inaccessible and isolated. Also, Fort Orange was much more important to the fur trade, even though the Hudson River froze solid as well.
In the 1890s, Charles Conrad Abbott conducted excavations on Burlington Island. The 196 artifacts he unearthed are now part of the Peabody Museum of Archaeology and Ethnology in Cambridge, Massachusetts. Listed under the provenience “Dutch Trader’s House,” they include shards of pottery roof tiles, red pottery pipe fragments, metal nails, glass fragments, glass beads, as well as faunal remains, and artifacts of Native American make. There is some doubt as to whether these finds, for which a mid seventeenth-century dating has been suggested, are connected with the 1620s fort on the lower end of the island, or rather with a 1650s trading house, when it was known as Matinnekonk Island. Later, in the twentieth century, Burlington Island was used as a sand and gravel quarry, which created a large lake in the middle of the island. Even so it is possible that remains of Fort Wilhelmus have survived on the southernmost tip of the island.
Wilhelmus, fort (Prince's island)
Wilhelmus, fort (Burlington Island)