Iran was largely Sunni until the Safavid dynasty imposed Shi’ism

Evidence

Shi‘ism was reintroduced and imposed by the Safavids many centuries later, and they, I would remind you, were Turks. Until then Iran was a largely Sunni country. But no doubt that with the establishment of the Shi‘ite Safavid state a new era began, one of a distinctively Iranian Shi‘ite character. — Bernard Lewis, From Babel to Dragomans, 304

Categorization

• XREF: Complicates the common assumption that Iran’s Shi’ism is ancient and autochthonous; connects to the general point that religious identities are often politically imposed rather than continuous.
• SHARE: A surprising fact for anyone interested in Iran — that its Shi’ism dates only to a 16th-century imposition by a Turkish dynasty, and Qomm was built by Arabs.