Note 7 — Chapter I · INTRODUCTION.
Reading edition
It was only in 1857 that the anomalous condition of Neuchâtel ceased. The rights of the kings of Prussia as sovereigns date back to the cession made of it in 1707 by William of Orange to his cousin Frederick, first King of Prussia. In 1806 it was granted as a principality to Marshal Berthier, and so recognized by all the powers of Continental Europe. The Congress of Vienna restored it to the King of Prussia, making it, however, a Canton of the Helvetian Republic. In 1848 a revolution forcibly overturned the authority of the King of Prussia, and it so remained, in apparent conflict to what had been formally recognized by all the Great Powers, until 1857, when a treaty was signed between Austria, France, Prussia, Russia, Great Britain, and Switzerland, by which it was made independent, to continue to form a part of the Swiss Confederation, by the same title as the other Cantons.