Shaykhism () is an Islamic religious movement founded by Shaykh Ahmad in early 19th-century Qajar Iran. While grounded in traditional pure 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 orthodox members of the Shiʻi ulama.