This occurred, for example, in the Holy Roman Empire, where three of the seven imperial electors were prince-archbishops (those of Trier, Mainz and Cologne).
After the 1648 Peace of Westphalia certain prince-bishoprics became bi-confessional and alternated between governance by Catholic bishops and by Protestant administrators.
The Supreme Leader of Iran is elected for life by a body consisting of senior Twelver Shia Muslim clerics.
The subsequent personal and legal unions with Wales, Scotland and Ireland did not extend Anglicanism's status of state church to these lands.
[5] Vatican City operates under an episcopal system, its head of state since the eighth century is the pope of the Catholic Church.