My dear Lord /u/xaxers,
The College of Electors is a noble an ancient institution, and its membership is defined by that most important of documents, the Golden Bull of 1356, which sets aside the key rules and laws which govern the Holy Roman Empire to this day! The Golden Bull established that there should be seven princes of the Empire who would have the right and duty to elect the King of the Romans, who would subsequently suceed as Holy Roman Emperor. These seven princes can be divided into the three Ecclesiastical Electors, and the four Secular Electors. The former were to be the Archbishops of Mainz, Trier, and Cologene, repectively, while the latter were to be represented by the King of Bohemia, our most gracious self; the Count Palatine on the Rhine--although this title has rightfully passed on to the Count's cousins, the Dukes of Bavaria, due to the treachery of that damnable outlaw, Frederick--the Duke of Saxony; and the Margrave of Brandenburg.
As Prince-Electors of the Empire, these seven enjoyed greater rights and privileges than the standard prince, and had a place of honour second only to the Emperor and those who hold the most noble title of Archduke--as confirmed by the Privilegium Maius.^1 They had several important rights and privileges, including: precedence over other princes; to be adressed as 'Serene Highness'; and the privilege of non-appeal, which prevented their subjects from appealing matters to the proper Imperial Courts where they should be held. They also held all the other rights and privileges of an Imperial estate holder.
The Golden Bull set the rules and procedures to be followed when the College of Electors gathered, either to elect a new Emperor, or to confirm the Emperor's heir--the King of the Romans. The Electors--or, more commonly, since the Electors were often busy with affairs of state, the representative of the Electors--would gather together to vote on candidates. Alas, this would often involve a great deal of politicking, with assurances and promises given to the electors to ensure that they knew to vote for the proper candidate. Once at least four of the seven electors agreed on a candidate, the Emperor-Elect would confirm the rights and privileges of the Princes, and the Emperor-Elect would be confirmed in his office.
Yours Most Sincerely,
Ferdinand II, by the grace of God elected Holy Roman Emperor, forever August, King in Germany, King of Hungary, Bohemia, Dalmatia, Croatia, Slavonia, Rama, Serbia, Galicia, Lodomeria, Cumania, Bulgaria, Archduke of Austria, Duke of Burgundy, Brabant, Styria, Carinthia, Carniola, Margrave of Moravia, Duke of Luxemburg, of the Higher and Lower Silesia, of Württemberg and Teck, Prince of Swabia, Count of Habsburg, Tyrol, Kyburg and Goritia, Marquess of the Holy Roman Empire, Burgovia, the Higher and Lower Lusace, Lord of the Marquisate of Slavonia, of Port Naon and Salines, etc. etc.
1: The Privilegium Maius is now known to be a forgery, designed to ensure that the dukes of Austria--who did not receive the rank or privileges of elector--would be held as at least 'equal' to the prince-electors in terms of precedence and other matters. The title 'Archduke' came to hold a great deal of weight and importance for the Habsburgs, who never proclaimed themselves as the 'King of Austria', even when no longer bound by the structure of the Holy Roman Empire, but rather continued to keep the title 'Archduke of Austria'.