Principality of Transylvania (1570–1711)
The Principality of Transylvania (Hungarian: Erdélyi Fejedelemség; Latin: Principatus Transsilvaniae; German: Fürstentum Siebenbürgen; Romanian: Principatul Transilvaniei / Principatul Ardealului; Turkish: Erdel Voyvodalığı / Transilvanya Prensliği) was a semi-independent state ruled by Hungarian princes. It existed as an Ottoman vassal state for the majority of the 16th and 17th centuries, overseen by Ottoman Turkish sultans.
Source: Wikipedia — Principality of Transylvania (1570–1711) (CC BY-SA 4.0)