their version of islam is as strict as the Shi’ite sect. referred to as “wahabi” and is a fundamentalist form of the “religion.”
In the 1700s Mohammad al Wahabb along with King Saud conquered the Arabian peninsula and as you said they got the backsliding Muslims who were bringing other religious trappings into Islam; back to the fundamentals of Islam as practiced by Muhammad-and Caliphs Abu Bakr -Umar-Uthman and Ali.
Wahhabism is a fundamental version of Sunni Islam. -Tom