Safavid Empire
The dynasty that seized Iran in 1501 and forcibly converted it to Twelver Shia Islam, creating the sectarian map of the modern Middle East.
In 1501 a fourteen-year-old boy named Ismail rode into Tabriz at the head of a tribal cavalry army, declared himself shah, and announced that Twelver Shia Islam was now the religion of the state. The land he had just taken was mostly Sunni. He converted it anyway, by decree, by imported clergy, and where necessary by execution. Two and a half centuries later Iran was the Shia country it remains today, and the border between Sunni and Shia in the Middle East runs roughly where the Safavids stopped.
A holy order that became an army
The Safavids began as a Sufi brotherhood in Ardabil, and Ismail was its hereditary master. His followers, Turcoman tribesmen from Anatolia and Azerbaijan, wore distinctive red caps and were known as the Qizilbash, the redheads. They regarded him as something close to divine, which is a useful quality in cavalry and a dangerous one in a state. Ismail wrote poetry in Turkish claiming exactly that status.
The problem with a messianic army is that defeat is theologically expensive. In 1514, at Chaldiran in eastern Anatolia, the Ottoman sultan Selim I met Ismail with janissary infantry and field guns. The Qizilbash charged cavalry into artillery and were slaughtered. Ismail never personally led an army again and reportedly drank heavily until his death ten years later.
Building a Shia state from scratch
Converting a country requires clergy, and Iran did not have enough Shia scholars. The Safavids imported them, principally from Jabal Amil in what is now southern Lebanon and from Bahrain, and endowed them with land, courts, and salaries. This was a fateful piece of institution-building. It created a professional Shia clerical class with its own money and its own hierarchy, answerable to the shah in practice but not in theory.
Shah Abbas I, who ruled from 1588 to 1629, completed the state. He broke the power of the Qizilbash tribes by building a standing army of ghulams, Caucasian slave-soldiers converted to Islam and loyal only to him, exactly as the Ottomans had done with the devshirme levy of Christian boys. He moved the capital to Isfahan in 1598 and rebuilt it around an enormous ceremonial square, and the city grew so splendid that Persians said Isfahan nesf-e jahan, Isfahan is half the world. He took the silk trade into royal monopoly and dealt directly with English and Dutch merchants to route it around Ottoman territory.
Collapse
The end was abrupt. In 1722 a force of Afghan tribesmen from Kandahar, perhaps twenty thousand men, besieged Isfahan for six months. The city starved, and Shah Sultan Husayn walked out and handed over his crown. The dynasty limped on as a puppet until the soldier Nader Shah pushed the Afghans out, ruled in the name of Safavid figureheads, and finally took the throne himself in 1736.
The inheritance
Iran is the only country on earth where Twelver Shia Islam is the established religion, and that is a Safavid decision, not an ancient fact. The rivalry that shapes the region, Iran against the Sunni Arab monarchies, runs along a line drawn by Safavid and Ottoman armies in the sixteenth century. And the clerical establishment the Safavids created to legitimize a monarchy outlived every monarchy it served. In 1979 it took the state for itself.