Towards the end of July 1619, the voters or their representatives had arrived in Frankfurt to take part in the Imperial Election.
The 31 July, Lusatia, Silesia and Moravia they entered into a federal agreement with the Bohemia in order to defend the national integrity.
On 19 August, the Confederate States of Bohemia, Lusatia, Silesia and Moravia had declared void the previous election of Ferdinand of Habsburg and sealed his loss of the throne of Bohemia.
On August 26, the Bohemians were summoned to elect a new king. Among the candidates there was, in addition to the Elector Frederick of the Palatinate, the Elector John George of Saxony. The candidate less dangerous was precisely the latter, but the Elector had immediately shown little sympathy for the revolt, but was respected for his prestige and his wisdom, and he would be able to reach a compromise with Ferdinand of Habsburgs. The choose Frederick of the Palatinate meant instead choose war to the bitter end with the serious risk of a disastrous defeat for the Bohemia.
However at the election prevailed the Protestant extremists and Frederick was elected king by 146 votes against 7.
At the Court of Heidelberg everyone had dissuaded Frederick to accept a crown so dangerous. His mother, Louise Juliana of Nassau, daughter of William of Orange, told him not to depart. His Council presented at him a list with fourteen reasons contrary to accept the crown, against six favorable. Even the sovereigns his allies advised him to avoid getting bogged down in the question Bohemian.
Two days after, took place at Frankfurt the Imperial election: news from Bohemia had not yet arrived, and Ferdinand took his place among voters as King of Bohemia, and in the end, he was elected emperor by a unanimous vote (even that of the Palatinate!).
On 28 September, Frederick of the Palatinate said to himself willing to accept the crown of Bohemia.
Suggestions on the hypothesis that the Elector of Saxony had accepted the throne of Bohemia?