 During the Greco-Turkish War (1919-1922), the nationalist Turkish authorities in an attempt to Turkify and take the Orthodox church under their full control, founded the Turkish Orthodox Church in Kayseri and installed Papa Eftim as its head.Prokopios was against these developments and tried to reach a solution concerning the administration of the Orthodox Church in Anatolia.In September 20, 1920, as a result of his intervention, Prokopios, as well as the local Armenian bishop of Konya, were imprisoned by the nationalist authorities of Mustafa Kemal.