The old Persian civilization. Not much left of that now.
Also political. From the Middle Ages until WWI virtually the entire Middle East was ruled by the relatively lax and corrupt Ottoman Turkish Caliphate. Like Turks today, these rulers were more pragmatic than fanatical--and they didn't tolerate Islamic fanatics.
In the closing years of the Ottoman Empire they did perpetrate one of the first great holocausts however...purposely murdering over 1 Million Armenian Christians--their own citizens--mainly just because they were Christian. This deliberate genocide has yet to be fully acknowleged by the Turkish government--and was largely perpetrated by the popular will of the Moslem populace--encouraged by their rulers, and the Immams.
If Europe wants to know what could happen when/if Moslem populations become a majority in their own countries, they need only look back to 1917.
Of course in modern times before the discovery (by Americans & Europeans) of oil in the Middle East, they were all dirt poor too. Money and Politics does change things.