For centuries, a handful of German princes chose the Holy Roman Emperor
The Holy Roman Emperor was not simply born to the job. A small college of princes, the Kurfürsten, voted for him, first by loose custom and from 1356 under a charter called the Golden Bull. Their title ranked just below kings, and it lasted until the empire itself ended in 1806.
The German word Kurfürst joins the Middle High German kure, choice, with Fürst, prince. From the 13th century a select group of electors held the right to choose the King of the Romans, whom a pope would afterwards crown as emperor. The last to get that papal ceremony was Charles V, chosen in 1519 and crowned in 1530; his successors styled themselves Elected Emperor of the Romans once crowned as kings. The heir of a secular elector was called the Kurprinz, or electoral prince.
Electors ranked behind only the emperor, kings and the greatest dukes, and they kept their original titles alongside the electoral one. Until the 18th century only they could be addressed as Serene Highness; in 1742 they moved up to Most Serene Highness while other princes took the old style. The Golden Bull gave them a privilege blocking their subjects from appealing to higher imperial courts, though larger states could obtain similar rights individually.
They also carried weight in the Imperial Diet, which had councils of electors, princes and cities. Because many electors ruled several territories or held church offices, they cast multiple votes among the princes: in 1792 Brandenburg alone had eight, and electors controlled twenty-nine of the hundred votes in that council. After the Peace of Westphalia the Diet could also vote by religion, with the Archbishop of Mainz leading the Catholic bloc and the Elector of Saxony the Protestant one.
When an emperor died, the Archbishop of Mainz had a month to summon the electors, who then had three months to meet, though often a successor had already been chosen during the old emperor's life. In any gap, two imperial vicars governed: Saxony over lands under Saxon law in the north, and the Elector Palatine over the south and the Rhine, a role Bavaria sometimes filled between 1623 and 1777.
Source: Prince-elector
