Między Szczecinem a Gryfią – główne wątki historiograficznej współpracy polsko-niemieckiej w drugiej połowie XX wieku

The factor that stimulated the thought of ethical justification of warfare in medieval Europe was among others expansion of Islam. At the beginning of the Islamic religion, its believers were deeply convinced by the ideas coming from the pages of Koran dictated by prophet Mohammed, the words which encouraged them to convert infidels. The fact is that during the lifetime of Mohammed, Muslims bent to their own will many Arabic tribes and just after his death they had a greater part of the Arabian Peninsula in their hands. In 711 they crossed the Strait of Gibraltar and started conquering the Iberian Peninsula. In the meantime, in Europe, people who, on account of their public role, were supposed to have a wider perspective of the world issues, were aware of the dangers which Islam caused. The fight for preservation of the Latin civilization caused thus far an unprecedented inner consolidation of armed, political and intellectual forces of those times. In this way the epoch of the crusades began.