Count John IV of Nassau-Siegen, German: Johann IV. Graf von Nassau-Siegen, official titles: Graf zu Nassau, Vianden und Diez, Herr zu Breda, was since 1442 Count of Nassau-Siegen, of Vianden and of half Diez, and Lord of Breda and of the Lek. He descended from the Ottonian Line of the House of Nassau.
- Occupation
- Count of Vianden, Count of Diez, Q2197443, military personnel
- Position held
- Marschal of Westphalia, Landdrost, castellan
- Born
- August 1, 1410
- Died
- February 3, 1475
