Complex sentence: The Al ash-Sheikh is Saudi Arabia's leading religious family and is descended from Muhammad ibn Abd al-Wahhab, the 18th century founder of the Wahhabi form of Sunni Islam which is today dominant in Saudi Arabia.
Split into simpler sentences: The Al ash-Sheikh (also transliterated as Al ash-Shaykh, Al al-Sheikh or Al al-Shaykh) is Saudi Arabia's leading religious family. They are the descendants of Muhammad ibn Abd al-Wahhab, the 18th century founder of the Wahhabi form of Sunni Islam which is today dominant in Saudi Arabia.