July 22, 2026
On July 22rd, former Dutch ambassador and Leiden University lecturer Piet de Klerk shared his research process and findings on his family history of the Wyckoff and Van Ness families. Using sources including the Holland Society’s digitized Vertical Files, de Klerk uncovered part of a new narrative of how the main actors came to New Netherland and the lives they led during this vibrant time in the Dutch colony. We thank Piet for also sharing his research guidelines and the tips and lessons he found helpful during his own research.
Piet followed the story of Pieter Claesen (later Wyckoff) and Grietje Van Ness. He began with the families’ origins in the Netherlands. Grietje’s grandparents came from an area where the closest town was Lexmond, and her parents, Cornelis and Maycken, lived in the town of Vianen in the province of Utrecht. In 1641, Cornelis and Maycken contacted Van Rensselaer that they would want to emigrate to his colony in New Netherland.
Pieter Claesen was born near Norden some time in the 1620s. At this time in East Frisia, the Thirty Years’ War was disrupting the area and further motivating residents to leave. Around 1636, Pieter was one of the emigrants who left for Amsterdam and then shortly after for New Netherland to work as an indentured laborer.
In 1637, Pieter arrived in New Amsterdam and made his way up to Fort Orange. On his long voyage to New Amsterdam, Pieter befriended one of the free farmers, Simon Walichs, and worked in agriculture rather than in the beaver trade.
After working the land on Papscanee Island, around 1643, Pieter gets a lease to his own land, and at the same time, Cornelis and Mayke arrive with Grietje as some of the new settlers to the area. Pieter and Grietje meet and are married in 1646. While Grietje’s parents stayed up the Hudson River in Greenbush, Pieter and Grietje moved to New Amsterdam in the summer of 1649. While it is unclear what their exact motivations were for moving there, they eventually settled on Long Island.
As Pieter and Grietje were on good terms with Peter Stuyvesant, Stuyvesant appointed Pieter as farm manager of the Van Twiller land, where the famous Wyckoff House still stands today. There, Pieter and Grietje raised six more children. By the end of their lives, the couple had become quite well off, with Piet becoming an alderman of the local village called Amersfoort in the Flatlands area until the British took over. They were both buried in the cemetery of the Flatlands church.
Click here to view the recording of the lecture.