Absolutely, except even more than the current level.
Imagine a place where fanatics roam the land, where wars were waged, people were killed, women raped, entire areas depopulated, entire cities massacred. Where people are not just harmed, but killed in the most gruesome manner possible, where leaders of supposedly holy beliefs use their power and authority to build harems for themselves, and of course, to purge any supposed unbelievers.
The place I'm talking about is, of course, Germany in the 1500-1600s.
The closest parallel to the modern period of violence associated with various Islamic sects is the period in Europe roughly known as the reformation and the eighty years war. When a holy book met increased literacy and economic development, and a revolt occurred against established religious order.This is what happened in Central Europe with the Lutherian and Calvanist reformation, and the wars of religion largely between Protestants and Catholics.
You had atrocities (at least partially religious motivated) such as the massacre of Magdeburg, when a Catholic army took a primarily Protestant city and killed over 80% of its inhabitants. The Thirty Years war, largely a war of Protestant against Catholics until its last phase, itself, with its roving armies of mercenaries who pillaged and murdered at will killed between 25%-40% of the entire population of the states which comprise of modern day Germany.
For an answer better than this please see this flaired user's post in another thread:
This submission has been removed because it involves current events. To keep from discussion of politics, we have a 20-year rule here. You may want to try /r/ask_politics or another current-events focused sub.