(1502–1736), Iranian dynasty whose establishment of Shīʿite Islām as the state religion of Iran was a major factor in the emergence of a unified national consciousness among the various ethnic and linguistic elements of the country. The Ṣafavids were descended from Sheykh Ṣafī od-Dīn (1253–1334) of Ardabīl, head of the Ṣūfī order of Ṣafavīyeh (Safawiyah), but about 1399 exchanged their Sunnite affiliation for Shīʿism.

The founder of the dynasty, Ismāʿīl I, as head of the Ṣūfīs of Ardabīl, won enough support from the local Turkmens and other disaffected heterodox tribes to enable him to capture Tabrīz from the Ak Koyunlu (Turkish: “White Sheep”), an Uzbek Turkmen confederation, and in July 1501 Ismāʿīl was enthroned as shah of Azerbaijan. By May of the next year he was shah of Iran. In the next 10 years he subjugated the greater part of Iran and annexed the Iraqi provinces of Baghdad and Mosul; despite the predominantly Sunnite character of this territory, he proclaimed Shīʿism the state religion.

In August 1514, Ismāʿīl was seriously defeated at Chāldirān (Chāldirān, Battle of) by his Sunnite rival, the Ottoman sultan Selim I. Thereafter, the continuing struggle against the Sunnites—the Ottomans in the west and the Uzbeks in the northeast—cost the Ṣafavids Kurdistan, Diyarbakır, and Baghdad; the Ṣafavid capital had to be temporarily relocated at Eṣfahān—permanently by about the early 17th century.

Iran weakened appreciably during the reign of Ismāʿīl's eldest son, Shah Ṭahmāsp I (1524–76), and persistent and unopposed Turkmen forays into the country increased under his incompetent successors. In 1588 Abbās Iʿ was brought to the throne. Realizing the limits of his military strength, ʿAbbās made peace with the Ottomans on unfavourable terms in 1590 and directed his onslaughts against the Uzbeks. Meeting with little success, ʿAbbās engaged (1599) the English Sir Robert Sherley to direct a major army reform. Three bodies of troops were formed, all trained and armed in the European manner and paid out of the royal treasury: the ghulāms (slaves), the tofangchīs (musketeers), and the topchīs (artillerymen).

With his new army, ʿAbbās defeated the Turks in 1603, forcing them to relinquish all the territory they had seized, and captured Baghdad. He also expelled (1602, 1622) the Portuguese traders who had seized the island of Hormuz in the Persian Gulf early in the 16th century.

Shah ʿAbbās' remarkable reign, with its striking military successes and efficient administrative system, raised Iran to the status of a great power. Trade with the West and industry expanded, communications improved; the capital, Eṣfahān, became the centre of Ṣafavid architectural achievement, manifest in the mosques Masjid-i Shāh and the Masjid-i Sheykh Loṭfollāh; and other monuments including the ʿAlī Qāpū, the Chehel Sotūn, and the Meydān-i Shāh. Despite the Ṣafavid Shīʿite zeal, Christians were tolerated and several missions and churches were built.

After the death of Shah ʿAbbās I (1629) the Ṣafavid dynasty lasted for about a century, but, except for an interlude during the reign of Shah ʿAbbās II (1642–66), it was a period of decline. Eṣfahān fell to the Ghilzai Afghans of Qandahār in 1722; seven years later Shah Ṭahmāsp II recovered Eṣfahān and ascended the throne, only to be deposed in 1732 by his Afshārid lieutenant Nāder Qolī Beg (the future Nāder Shah).