Actually the Peace of Westphalia arranged truce between Lutherans and Roman Catholics but left other sects such as the Anabaptists unprotected and subject to vicious oppression resulting in a substantial migration of the German Anabaptists, Mennonites, Amish etc to Pennsylvania and down into Virginia beginning at the turn of the 18th century.
Many of them followed the same path as the Pilgrims had a century earlier seeking refuge first in Holland and then going on to the New World.
The period you are thinking of as 100 years long was this side of 50 years. Once the Swedes (The Great Protector of the North) were pinned down some Protestants found themselves in dispute with their Catholic nobles, but it was with their own nobles in their own countries, not kings elsewhere.
Remember, this went both ways ~ and plenty of Catholics found themselves under German nobles.
The Pope signed, but as a terrestrial ruler. All the other rulers signed as terrestrial rulers as well. I've looked over those pages of signatures ~ trying to figure out who each one was in reality.
Little did they know they were become famous for the ages.
A note ~ I've been working my way through the history of the Carpathians. These mountains end as a distinct geographic region right at the lip of the great crater that deines Bohemia, so, in effect, the political region (the ridge line) runs from France (if you count the Alps as part of the region) to Ukraine. Right smack in the middle of this thousand mile long line East to West, are the great silver mines where the Thaler was developed as a leading European currency.
One of the first actions of the Swedes even before the 30 years war was to move mining companies South into these mountains to see if there was more stuff and there was. There still is. The Czar actually cleared the population out of the Carpathians and replaced the people with Kossacks,.