Early modern period
In the early modern period, the Holy Roman Empire was a union of territories in Central Europe under a Holy Roman Emperor the first of which was Otto I. The last was Francis II, who abdicated and dissolved the Empire in 1806 during the Napoleonic Wars. Despite its name, for much of its history the Empire did not include Rome within its borders.
State church of the Roman Empire
By 476 the Germanic chieftain Odoacer had conquered Italy and deposed the last western emperor, Romulus Augustus, though he nominally submitted to the authority of Constantinople. The Arian Germanic tribes established their own systems of churches and bishops in the western provinces but were generally tolerant of the population who chose to remain in communion with the imperial church.