Mata Hari (born Margaretha Geertruida Zelle, August 7, 1876, in Leeuwarden, Friesland), infamous dancer, courtesan; executed as a spy in France, October 1917
Joost Klein (born November 10, 1997 in Leeuwarden, Friesland), Dutch musician, rapper, singer and former Youtuber
Wilhelm von Knyphausen (1716–1800), general from Hesse-Cassel; fought in the American Revolutionary War, during which he led Hessian mercenaries on behalf of the British Empire
Tjalling Koopmans (1910–1985), Dutch American mathematician and economist; Nobel Prize Laureate in Economic Sciences
Anna-Marie Lampe, Playboy magazine (US edition) 40th anniversary Playmate/Playmate of the Month for January 1994; Playboy magazine (Dutch edition) Playmate of the year for 1995
Theodor Mommsen (1817–1903), received the Nobel Prize in Literature in 1902; German politician, member of the Prussian and German parliaments
Hans Momsen (1735–1811), North Frisian farmer, layman mathematician and astronomer
F. W. Matthiessen (1835-1918) Born in Altona, Denmark, Descendant of Matthias Petersen (Matthias der Gluckliche), co-founder of Matthiessen and Hegeler Zinc Works in LaSalle, IL (USA), Founder of Westclox (now General Time), Philanthropist, Matthiessen State Park Deer Park, IL (USA)
Hark Olufs (1708–1754), sailor from Amrum; was enslaved by Algerian pirates; eventually became Commander in Chief of the Bey of Constantine's cavalry