This occurred especially from about A.D. 600 onward, when the Bishop of Rome first appropriated the title of Pope — and when Mohammad first embraced Islam. It climaxed around A.D. 1215, when the Romish doctrine of transubstantiation was enunciated officially. Then, after Islam had suppressed Christianity from Central Asia through North Africa and Spain as far as France — Mohammad II’s Turks in A.D. 1453 conquered Constantinople the capital of the Eastern Roman Empire and then started infiltrating northward through Albania, Bosnia, Bulgaria, Hungary, Poland, the Ukraine, and even Lithuania.