Mongol conquest of the Khwarazmian Empire in the context of "Mongol military tactics and organization"

The Anushtegin dynasty or Anushteginids (English: /ænuʃtəˈɡinid/, Persian: خاندان انوشتکین), also known as the Khwarazmian dynasty (Persian: خوارزمشاهیان) was a Sunni Muslim dynasty of Turkic mamluk origin from the Bekdili clan of the Oghuz Turks. The Anushteginid dynasty ruled the Khwarazmian Empire, consisting in large parts of present-day Central Asia, Afghanistan and Iran in the approximate period of 1077 to 1231, first as vassals of the Seljuks and the Qara Khitai (Western Liao), and later as independent rulers, up until the Mongol conquest of the Khwarazmian Empire in the 13th century.

The dynasty was founded by commander Anushtegin Gharchai, a former Turkic slave of the Seljuq sultans, who was appointed as governor of Khwarazm. His son, Qutb ad-Din Muhammad I, became the first hereditary Shah of Khwarazm. Anush Tigin may have belonged to either the Begdili tribe of the Oghuz Turks or to Chigil, Khalaj, Qipchaq, Qangly, or Uyghurs.

The Mongol invasions of Georgia (Georgian: მონღოლთა ლაშქრობები საქართველოში, romanized: mongholta lashkrobebi sakartveloshi), which at that time consisted of Georgia proper, Armenia, and much of the Caucasus, involved multiple invasions and large-scale raids throughout the 13th century. The Mongol Empire first appeared in the Caucasus in 1220 as generals Subutai and Jebe pursued Muhammad II of Khwarezm during the destruction of the Khwarezmian Empire. After a series of raids in which they defeated the combined Georgian and Armenian armies, Subutai and Jebe continued north to invade Kievan Rus'.

A full-scale Mongol conquest of the Caucasus and eastern Anatolia began in 1236, in which the Kingdom of Georgia, the Sultanate of Rum, and the Empire of Trebizond were subjugated, the Armenian Kingdom of Cilicia and other Crusader states voluntarily accepted Mongol vassalage, and the Assassins were eliminated. Mongol rule in the Caucasus lasted until the late 1330s. During that period, King George V the Brilliant restored the kingdom of Georgia for a brief period before it finally disintegrated due to Timur's invasions of Georgia.

The siege of Samarkand took place in March 1220 after Genghis Khan, founder of the Mongol Empire, had launched a multi-pronged invasion of the Khwarazmian Empire, ruled by Shah Muhammad II. The Mongols had laid siege to the border town of Otrar, but finding its defences obdurate, a large force commanded by Genghis and his youngest son Tolui detached from the vanguard and set off southwards, towards Transoxiana.

Samarkand was the Shah's capital and the pivot of his defence — the city's garrison was large and its battlements were one of the strongest in the empire. Genghis, however, managed to isolate it by capturing and destroying Bukhara in a surprise manoeuvre, and then laying waste to the nearby Transoxianan towns. After repelling relief forces, the Mongol army, now reinforced after the capture of Otrar, ambushed and massacred a sortie by the town's defenders. The citizens of the city soon surrendered at the instigation of the Muslim clergy; most were however enslaved or conscripted in traditional Mongol fashion.

Jalal al-Din Mangburni (Persian: جلال الدین مِنکُبِرنی), also known as Jalal al-Din Khwarazmshah (جلال الدین خوارزمشاه), was the last Khwarazmshah of the Anushtegin dynasty. The eldest son and successor of Ala ad-Din Muhammad II of the Khwarazmian Empire, Jalal al-Din was brought up at Gurganj, the wealthy capital of the Khwarazmid homeland. An able general, he served as second-in-command to his father in at least one battle; however, since he was the son of a concubine, he was challenged as successor by a younger brother, whose cause was supported by the powerful Queen Mother, Terken Khatun. Nevertheless, after the Mongol conquest of the Khwarazmian Empire led to his father's flight and death on an island in the Caspian Sea, Jalal-al Din gained the loyalty of the majority of Khwarazmian loyalists.

The new Shah Jalal al-Din moved to Gurganj, but departed eastwards after Terken Khatun moved against him; evading Mongol patrols, he gathered a substantial army at Ghazni. He managed to inflict an excellent defeat on Shigi Qutuqu at the Battle of Parwan, but soon lost a good portion of his army in a dispute over spoils. He was defeated by a vengeful Genghis Khan at the Battle of the Indus, and fled across the river. Now essentially a warlord, Jalal al-Din managed to establish a succession of short-lived states: first in the Punjab from 1222 to 1224, and then in northwest Iran and Georgia after 1225. Jalal al-Din did not have the political ability needed to underpin his martial exploits, and he was forced to combat several large revolts and increasing pressure from Mongol forces. Eventually, he was killed in 15 August 1231. The army he had gathered would continue to terrorize the Levant as the mercenary Khwarazmiyya until its final defeat in 1246.

The Mongol Empire conquered the Qara Khitai (Western Liao Empire) in the year 1218 AD. Prior to the invasion, war with the Khwarazmian Empire and the usurpation of power by the Naiman prince Kuchlug had weakened the Qara Khitai. When Kuchlug besieged Almaliq, a city belonging to the Karluks, vassals of the Mongol Empire, and killed their ruler Ozar, who was a grandson-in-law to Genghis Khan, Genghis Khan dispatched a force under command of Jebe and Barchuk to pursue Kuchlug. After his force of over 30,000 was defeated by Jebe at the Khitan capital Balasagun, Kuchlug faced rebellions over his unpopular rule, forcing him to flee to modern Afghanistan, where he was captured by hunters in 1218. The hunters turned Kuchlug over to the Mongols who beheaded him. Upon defeating the Qara Khitai, the Mongols now had a direct border with the Khwarazmian Empire, which they would soon invade in 1219.

The Irghiz River skirmish was a minor engagement fought between forces of the Khwarazmian Empire and the Mongol Empire during the early 13th century. While the occurrence of the skirmish itself is well-attested, its precise dating is uncertain, since the major chroniclers of the period give differing accounts. Modern historians have proposed two possible dates: 1209 or 1219. The background events are similar for each possible date: Genghis Khan, khagan of the Mongols, sent an army under his general Subutai to attack hostile forces (either a Merkit confederation or the renegade Naiman prince Kuchlug) in the former lands of the Qara-Khitai dynasty. Shah Muhammad, the ruler of the Khwarazmian Empire, received news of large armies operating along his northern borders and set out to confront them.

The Mongol army, which possibly also included the general Jebe and Genghis' eldest son Jochi, was surprised by the Shah very soon after defeating their initial target; Muhammad rejected peace overtures and initiated battle. The fierce engagement, between two armies of approximately equal strength, lasted until nightfall, but the Mongols probably had the upper hand. However, since they had been instructed to avoid any possible fighting, they abandoned their camp in secret during the night. The prowess of the Mongol soldiers displayed during the skirmish has been cited as a major reason for the Shah choosing a defensive strategy during the open warfare of 1220–21, for which this was a preliminary encounter.

The Khwarazmian army, also called the Khwarazmiyya, maintained itself as a force of freebooters and mercenaries between 1231 and 1246, following the Mongol conquest of the Khwarazmian Empire (1221) and the death of the last Khwarazmshah, Jalal al-Din (1231). It was active in Upper Mesopotamia, Anatolia, Syria and Palestine and shifted its allegiance several times, often acting autonomously before it was defeated and destroyed by the Ayyubids.

In 1231, the Khwarazmians were briefly in the service of the Ayyubid governors around Lake Van. Between 1231 and 1237, they were in the service of the Seljukid sultanate of Rum and fought against an Ayyubid invasion in 1232–1233. The Khwarazmians were forced back into Upper Mesopotamia in 1237, during a Seljukid succession crisis. They were then hired by the Ayyubid emir of Damascus. Taking part in the Ayyubid civil wars in Syria, they launched invasions against the emir of Aleppo in 1240 and 1241. Defeated in their second invasion, they retreated to central Mesopotamia and took service with the Abbasid caliphate. Later in 1241, the Khwarazmians hired themselves out to the Zengid emir of Mosul before returning to Syrian Ayyubid politics. They were defeated by Aleppo in 1242.