Countess Juliana of Nassau-Siegen was a noblewoman born in 1620, part of the House of Nassau. She was the daughter of Count John VII of Nassau-Siegen and Countess Anna of Nassau-Dillenburg. Juliana is known for her marriage to Count William of Nassau-Siegen, which strengthened the ties between their noble families. Throughout her life, Juliana was involved in various charitable activities and supported the arts. She passed away in 1688, leaving behind a legacy of cultural contributions and familial alliances that were significant in the Holy Roman Empire during her time.