Reichskrieg

A Reichskrieg ("Imperial War", pl. Reichskriege) was a war fought by the Holy Roman Empire as a whole against an opponent. After the Peace of Westphalia in 1648, a Reichskrieg was a formal state of war that could only be declared by the Imperial Diet.

There were two kinds of Reichskrieg with two different legal bases. The first was a Reichsexekutionskrieg, a military action of the empire against one of its own Imperial Estates (Reichstände). This could only be done after one of the empire's two supreme courts, the Imperial Chamber Court or the Imperial Aulic Council, had found the offending estate to be in breach of the peace, and the estate was too powerful to be subdued by the Imperial Circle to which it belonged. The second kind of Reichskrieg was that against an another sovereign state that had violated the empire's rights or frontiers. After 1519, the emperors were bound to get the support of the Imperial Electors prior to declaring war on another state. From 1648, they required the approval of the diet for both kinds of war.

The only state against which a formal Reichskrieg was ever declared was France. The diet declared war on France in 1689, 1702, 1734, 1793 and 1799. The declaration created a state of war, but it was still necessary for the emperor by a series of orders to begin the decentralised process of forming the Reichsarmee (Imperial Army) out of the Imperial Circles' troops. What each estate owed in both money and men was determined by the Imperial Military Constitution.

In the Middle Ages, the formal mechanisms of imperial war did not yet exist. Historians still sometimes speak of imperial wars, such as that declared by the Emperor Sigismund against duke Philip the Good of Burgundy in 1434, or that declared against the Armagnacs by the Emperor Frederick III in 1444.

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