The Holy Roman Empire represents the Church stepping in to fill the gap left by the crumbling Roman Empire lest society fall into chaos. The Church had its own courts, schools, authority structure.
If the Church had not supported European civil society as it did, we may not be here.
The Crusades were intially, though they certainly veered off into the obscene and immoral, an attempt to protect Christian pilgrims and residents in the 'holy land' who were being persecuted and murdered by Muslims.
There is no analog in either Christianity or Judaism, including the call for the conquest of the Canannites in Joshua, that stands alongside the Qu'ranic injunction to wage jihad until the entire world and all peoples are submitted and subjugated by violence to Islam. None.