List of Emperors of The Holy Roman Empire (The Kalmar Union)

The office of Holy Roman Emperor is normally dated from the the reign of the first elected Emperor Otto I, though the regnal numbers are dated from the reign of Charlemagne.

Dates of reign are taken from date of election to date of death/abdication. However these are often misleading, as some emperors would have their preferred successors 'pre-elected', while other claimants would have to endure long military campaigns before they could successfully have themselves crowned. Moreover, many elected emperors were simply never properly crowned.

Since the Fifty Years War no emperor has been crowned by the pope. Instead, coronation by either the Archbishop of Cologne or Archbishop of Milan depending on the candidate's religious confession is deemed sufficient. Separate ceremonies to confer the titles of King of Germany and King of Italy are conducted before the imperial coronation.

Schmalkaldic Empire
The Schmalkaldic Empire was proclaimed in 1558 as a union of the Lutheran states of Germany, with the addition of various Kalmar Union states. It had the same structure as the Holy Roman Empire i.e. in elections (with its own electoral counterpart) but utterly rejected any papal influence. It was essentially disbanded in 1639 during the course of the Fifty Years War. In 1668, as part of the Treaty of Copenhagen, all German Schmalkaldic territory officially re-integrated with the Holy Roman Empire. The German lands still subject to Denmark would become a major bone of contention for future rulers of both Denmark and the Holy Roman Empire.

The Schmalkaldic Empire was held by successive Danish kings for its entire duration.