The Principality of Transylvania is established after John II Zápolya renounces his claim as King of Hungary in the Treaty of Speyer.

The Principality of Transylvania 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. At various points during this period, the Habsburgs also exerted a degree of…