Willem van der Lely

Other name: 
Lelij, Guilielmus
estate executor
Birth or Baptism date: 
October 14, 1698
Death or Burial date: 
April 2, 1772

Willem van der Lely and Joris Geesteranus were the notaries who made the inventory of Maria van Leeuwenhoek's estate in 1645.

Van der Lely was baptized in Rotterdam, where his father was a magistrate for some of the surrounding areas (Cool and Schieland), and he probably grew up there.

He moved to Leiden to study in 1717; he graduated in 1720. He did not become a citizen of Delft until 1723, the year Leeuwenhoek died. He lived most of his life at Koornmarkt 77.

Civic life

In 1724, van der Lely became a notary. Two years later, he joined the civic guard and became a member of the Ridderlijke Confrérie. He worked as secretary of some of Delft's outlying areas (Vrijeban, Biesland, ’t Wout, Groenevelt, Zouteveen, Lier, etc.). In 1733 was appointed a regent of the Kamer van Charitate.

In 1738, he joined the Veertigraad, and the following year began his twenty years of service as the city's treasurer. It was during this time that he was involved with the estate of Maria van Leeuwenhoek.

Later, van der Lely was mayor (1760, 1761, 1765, 1766) and Delft's representative to provincial and national councils.

We remember him today for his work in genealogy and heraldry. His life's work is available in the Delft city archive: 21 books of coats of arms with about 11,000 examples (below right; click to enlarge), drawn by him, mostly in color, many with descriptions and explanations.


His wife, Geertruy van Heemskerk van Beest (1717-1775), was a regent of the Oude Mannen - en Vrouwenhuis in 1755. She was also among the first regents of the Fundatie van Renswoude, established by Leeuwenhoek's friend Maria Duyst van Voorhout.

Van der Lely's sister Maria Apolonia (1703-1769) married Gerard van Assendelft in 1723. His name is often mentioned right after van der Lely's in notary documents.

In 1746, Salomon van Groenewegen (-1757) married Maria Magdalena van der Lely, the daughter of Jacob van der Lely and Maria Magdalena van Assendelft (m 1720). In 1758, Maria Magdalena married Baron Nicolaus Albertus de Pouilly De Ginsvrij.