Council of Princes

The Imperial Diet (Latin: Dieta Imperii or Comitium Imperiale; German: Reichstag) was the deliberative and legislative body of the Holy Roman Empire. Its members were the Imperial Estates, divided into three colleges. The diet as a permanent, regularized institution evolved from the Hoftage (court assemblies) of the Middle Ages. From 1663 until the end of the empire in 1806, it was in permanent session at Regensburg.

The Imperial Estates had, according to feudal law, no authority above them besides the Holy Roman Emperor (or emperor-elect) himself. The holding of an Imperial Estate entitled one to a vote in the diet. Thus, an individual member might have multiple votes and votes in different colleges. In general, members did not attend the permanent diet at Regensburg, but sent representatives instead. The late imperial diet was in effect a permanent meeting of ambassadors between the Estates.

The precise role and function of the Imperial Diet changed over the centuries, as did the Empire itself, in that the estates and separate territories gained more and more control of their own affairs at the expense of imperial power. Initially, there was neither a fixed time nor location for the Diet. It started as a convention of the dukes of the old Germanic tribes that formed the Frankish kingdom when important decisions had to be made, and was probably based on the old Germanic law whereby each leader relied on the support of his leading men. For example, already under Emperor Charlemagne during the Saxon Wars, the Diet, according to the Royal Frankish Annals, met at Paderborn in 777, and the Diet of Aix in 802/803 officially determined the laws concerning the subdued Saxons and other tribes.

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