Shaykhism (الشيخية) is a Shi'a Islamic school founded by Shaykh Ahmad in early 19th-century Qajar Iran. While grounded in traditional Twelver Shiʻi doctrine, Shaykhism diverged from the Usuli school in its interpretation of key ideas such as the nature of the end times and the day of resurrection, the source of jurisprudential authority, and the proper hermeneutic to be employed in interpreting prophecy through the mystical writings of the Twelver Imams. These divergences resulted in controversy and ongoing accusations of heresy from Usulis and Akhbaris. It has been described as a mystical strand of Twelver Shi'a Islam. there remained a following in Iran, Iraq Saudi Arabia, Kuwait and Pakistan. The primary force behind Ahmad's teachings is the belief in the occultation of the Twelfth Imam. Believers in this doctrine, hold that the last divine ordained leader, or Imam, lives in occultation and will reappear as the promised Mahdi. Following the Mahdi's appearance, Ahmad teaches that the Imam Hussain ibn Ali will return to re-conquer the world and that the Imam Ali and prophet Muhammad will kill Satan. Al Raj'a (meaning "the return" in English) was heavily emphasized by Ahmad and is more important in Shaykhism than in the Usuli school of Islam. Shaykh Ahmad's perspectives on accepted Islamic doctrines diverged in several areas, most notably on his mystical interpretation of prophesy. The sun, moon and stars of the Qurʼan's eschatological surahs are seen as allegorical, similar to Ismaili doctrine, where common Muslim interpretation is that events involving celestial bodies will happen literally at the Day of Judgment. In an effort to "harmonize reason and religion" and "explain some doctrines of Islam that appear contrary to reason" and the laws of the natural world, Shaykh Ahmad, postulated an intermediary world between the physical and spiritual worlds that he called hurqalya.