Hendrik Brugt Gerhard Casimir (Den Haag, 1909 - Leiden, May 4, 2000).

Dutch nuclear physicist. In 1931, Casimir received his PhD at the University of Leiden, one of the centers of physics research in the world, as evidenced by the Nobel prizes for Van der Waals, Kamerlingh Onnes, and H. A. Lorentz. He then joined lighting factory Philips and was the main driving force behind its research center, Philips Natlab.

In 1948, Casimir predicted the Casimir effect on theoretical grounds; it was later verified experimentally.

Also, the name of several stadhouders of Groningen and Friesland:
Hendrik Casimir I van Nassau - van Dietz
(born Jan 31, 1612, Arnhem, died Jul 12, 1640, Hulst) became stadhouder in 1632
Hendrik Casimir II van Nassau - van Dietz
(born Jan 28, 1657, Leeuwarden, died Mar 25, 1696, Leeuwarden), his nephew, became stadhouder in 1664