 Even after the Palatinate had been awarded to the Kingdom of Bavaria at the Congress of Vienna, Welchweiler still belonged to the Canton of Wolfstein, but now this lay within the "Landcommissariat" of Kusel – later the "Bezirksamt" of Kusel, and later still the "Landkreis" (“rural district” – the designation it still bears today) of Kusel.Throughout Bavarian times (the kingdom came to an end with the German Kaiser's and the Bavarian king's abdications in 1918), Weimar times, the Third Reich and even into West German times up until 1968 – by which time Welchweiler found itself in the state of Rhineland-Palatinate – the village belonged to the "Bürgermeisterei" (“Mayoralty”) of Horschbach.In the late 1920s and early 1930s, the Nazi Party (NSDAP) became quite popular in Welchweiler, although support was not high early on.