You Can't Understand ISIS If You Don't Know the History of Wahhabism in Saudi Arabia
http://www.huffingtonpost.com/alastair-crooke/isis-wahhabism-saudi-arabia_b_5717157.html?ncid=fcbklnkushpmg00000051&ir=Religion
--snip
But this "cultural revolution" was no docile reformism. It was a revolution based on Abd al-Wahhab's Jacobin-like hatred for the putrescence and deviationism that he perceived all about him -- hence his call to purge Islam of all its heresies and idolatries.
MUSLIM IMPOSTORS
The American author and journalist, Steven Coll, has written how this austere and censorious disciple of the 14th century scholar Ibn Taymiyyah, Abd al-Wahhab, despised "the decorous, arty, tobacco smoking, hashish imbibing, drum pounding Egyptian and Ottoman nobility who travelled across Arabia to pray at Mecca."
In Abd al-Wahhab's view, these were not Muslims; they were imposters masquerading as Muslims. Nor, indeed, did he find the behavior of local Bedouin Arabs much better. They aggravated Abd al-Wahhab by their honoring of saints, by their erecting of tombstones, and their "superstition" (e.g. revering graves or places that were deemed particularly imbued with the divine).
All this behavior, Abd al-Wahhab denounced as bida -- forbidden by God.