Electing the Emperor
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Emperors,once chosen, serve for life. However, if the emperor is vassalized, forced intoa personal union, or otherwise annexed, a new emperor will be elected. On thedeath of the current Emperor, the Imperial Electors choose a replacement from within the Christian world.
An Emperor can only be selected from candidates that are:
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Male (NB:Austria can get an event that removes this requirement permanently if they havea female heir)
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Christian
I
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ndependent rulers (i.e. not a vassal)
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Monarchs (i.e. not rulers of republics or theocracies)