Treaty of Neuilly-sur-Seine
After the capitulation of Bulgaria and the end of the First World War, the area returned under Belgrade control as part of the newly formed Kingdom of Serbs, Croats and Slovenes and saw a reintroduction of anti-Bulgarian measures. Bulgarian teachers and clergy were expelled, Bulgarian language signs and books removed, and all Bulgarian organisations dissolved. Also after the Treaty of Neuilly-sur-Seine, Strumica region was annexed to Serbian Macedonia in 1919.