Neuchâtel Crisis

[1] Neuchâtel was returned to Frederick William in 1814, and the following year he agreed to allow the Principality to join the Swiss Confederation (which was then an alliance of semi-independent states rather than a single country) while remaining under his rule.

[2][1] Despite the success of the 1848 revolution, the situation in Neuchâtel remained tense as a strong royalist opposition, supported by Prussia, faced the new government.

[1] Switzerland sent federal councilors Constant Fornerod and Friedrich Frey-Herosé as commissioners to Neuchâtel, alongside investigating judge Charles Duplan.

[1] After unsuccessful French and British attempts at mediation, on 13 December 1856 Prussia severed diplomatic relations with Switzerland and scheduled the mobilization of its army for 1 January 1857.

[1] Nevertheless, on the request of Napoleon III, Prussia postponed its mobilization to 15 January, then cancelled it entirely after the French emperor obtained from the Federal Council the release, and expulsion from Switzerland, of all royalist prisoners.