Electorate of Trier
The Electorate of Trier was an ecclesiastical principality of the Holy Roman Empire that existed from the end of the 9th to the early 19th century. It was the temporal possession of the prince-archbishop of Trier who was, ex officio, a prince-elector of the empire. The other ecclesiastical electors were the archbishops (in the secular context called simply electors) of Cologne and Mainz.
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