The Heiliges Romisches Reich or Sacrum Romanum Imperium (Holy Roman Empire) was a political entity created by the papacy. Ruled first by the Frankish kings and then by the German kings, it existed for ten centuries and included what is now Germany, Austria, the Czech Republic, Switzerland, eastern France, the Low Countries, and northern and central Italy. Pope Leo III first conferred the title of king of the Romans on Charlemagne in 800. (The term Holy Roman Emperor was actually never used; it is a convention adopted by modern historians.)

Originally an instrument of the papacy, the Holy Roman Empire developed into a rival. Between the. mid eleventh century and mid thirteenth century the empire and the papacy vied for control of Christian Europe. By the early 1400s the imperial title became virtually hereditary in the Austrian house of Habsburg. Following...