The Bishopric of Speyer (formerly known as Spires in English) was an ecclesiastical principality in what is today the German state of Rhineland-Palatinate. It was secularized in 1803. The prince-bishop resided in Speyer, a Free Imperial City, until the 14th century when he moved his residence to Uddenheim (Philippsburg) then Bruchsal in large part due to the tense relationship between successive prince-bishops and the civic authorities of the Free City, officially Protestant since the Reformation. The prince-provostry of Wissemburg in Alsace was ruled by the prince-bishop of Speyer in a personal union relationship.
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