Battles & Wars › Medieval wars › Mongol conquests
Mongol conquest of Khwarazm (Bukhara and Samarkand)
1219–1221; Bukhara and Samarkand fell 1220· War· Asia & Pacific
Well documentedSolid records, physical evidence or scientific consensus.
Genghis Khan's 1219–1221 invasion that destroyed the Khwarazmian Empire, the leading Muslim power of Central Asia and Iran.
See it on the Battles & Wars map →What happened
In 1218 a governor of the Khwarazmian Empire massacred a Mongol-sponsored trade caravan at Otrar, and Shah Muhammad II had a Mongol envoy killed. Genghis Khan invaded in 1219. His columns split up, taking Otrar, then Bukhara and Samarkand in 1220, and Urgench, Merv and Nishapur in 1221. Cities that surrendered were often spared; those that resisted were destroyed, and their craftsmen were deported east. The shah fled and died on an island in the Caspian Sea.
Why it matters
It wiped out Central Asia's leading Muslim power in three years, opened Iran and the Middle East to the Mongols, and ruined cities and irrigation systems that took centuries to recover.
How we know
Persian historians Juvaini, who served the Mongols, Juzjani and Rashid al-Din; the Arab historian Ibn al-Athir, who wrote of the terror; the Secret History of the Mongols; and excavations at Merv and Otrar.
Still debated
Death tolls are estimates that vary widely. Chroniclers' figures of over a million dead at single cities are thought exaggerated, but losses were enormous.
Inside this (1)
Connections (4)
▸Battle of Talas helped tilt Central Asia toward Islam before the Mongol conquest of Khwarazm (Bukhara and Samarkand)Debated
The connection
At Talas in 751 an Abbasid army beat a Tang Chinese force. China soon withdrew from Central Asia, mostly because of its own An Lushan rebellion, and over the next centuries the region became Muslim. By 1219 its great Muslim cities, Bukhara and Samarkand, were the heart of the Khwarazmian Empire that the Mongols destroyed.
When and how
Talas River, on today's Kyrgyzstan–Kazakhstan border, July 751; Bukhara and Samarkand, in today's Uzbekistan, 1220.
How sure are we?
Both events are well recorded. The link is a long-run one, spanning nearly five centuries of conversion, not a direct cause.
Debates and open questions
How much Talas mattered is debated: many historians think Islam would have spread anyway, and the Tang retreat owed more to the An Lushan rebellion.
▸Genghis Khan avenged his murdered envoys in Mongol conquest of Khwarazm (Bukhara and Samarkand)Well documented
The connection
Genghis sought trade with Khwarazm. In 1218 the governor of Otrar massacred a Mongol-sponsored caravan of several hundred merchants, and Shah Muhammad II executed an envoy sent to demand justice. Genghis answered with a full invasion in 1219, commanding it himself with his sons.
When and how
Otrar, on the Syr Darya in today's Kazakhstan, 1218; invasion 1219–1221 by Genghis, his sons Jochi, Chagatai, Ögedei and Tolui, and generals Jebe and Subutai.
How we know
Juvaini, Juzjani and Ibn al-Athir all describe the Otrar massacre and the killing of the envoy as the cause of the war.
Debates and open questions
Some historians think Genghis would have attacked anyway and the incident was a pretext; the caravan may also have carried spies.
▸Mongol conquest of Khwarazm (Bukhara and Samarkand) climaxed at Battle of the IndusWell documented
The connection
After Shah Muhammad II died in flight, his son Jalal al-Din kept fighting from Afghanistan and beat a Mongol army at Parwan. Genghis Khan pursued him to the Indus, where the last Khwarazmian field army was destroyed, effectively ending the campaign.
When and how
Parwan, Afghanistan, 1221; Indus River, in today's Pakistan, November 1221.
How we know
Persian chroniclers and Jalal al-Din's secretary Nasawi describe the sequence from Parwan to the Indus.
Debates and open questions
The exact site and date are uncertain. Jalal al-Din kept fighting in Iran and the Caucasus until 1231, so the war's 'end' is relative.
▸Mongol conquest of Khwarazm (Bukhara and Samarkand) opened the Islamic heartlands to the later Siege of Baghdad (1258)Mostly agreed
The connection
Destroying Khwarazm removed the only great Muslim power between Mongolia and the Middle East, and Mongol armies then held much of Iran. In the 1250s Hülegü, Genghis's grandson, used that base to destroy the Assassins' castles and take Baghdad, ending the Abbasid caliphate.
When and how
Central Asia and Iran, 1219–1221; Hülegü's campaign 1253–1260, with Baghdad taken in February 1258.
How sure are we?
Persian historians, notably Juvaini, who served Hülegü, describe the campaigns as one continuing Mongol conquest of Iran.
Debates and open questions
Historians debate how far Mongol rule in Iran also brought trade and learning, and how to weigh that against the destruction.