In 1815, in the wake of Napoleon’s downfall and the Congress of Vienna, French rule ended and Schmidthachenbach found itself in the Duchy of Saxe-Coburg-Saalfeld while remaining a "mairie" – although now called a "Bürgermeisterei", the German word for the same thing – within the constituent territory of the Principality of Lichtenberg with Sankt Wendel as its capital. In 1834, Saxe-Coburg-Saalfeld sold the Principality of Lichtenberg to the Kingdom of Prussia, and it became the Sankt Wendel district. At the time when the German Empire was founded in 1871, Schmidthachenbach had 466 inhabitants. The “Peace Oak” was also planted near the church this year on the occasion of the end of the Franco-Prussian War.