Genghis Khan, National Palace Museum in Taipei, Taiwan
Among his first actions, Ögedei sent troops to subjugate the Bashkirs, Bulgars, and other nations in the Kipchak-controlled steppes. In the east, Ögedei's armies re-established Mongol authority in Manchuria, crushing the Eastern Xia regime and Water Tatars. In 1230, the Great Khan personally led his army in the campaign against the Jin dynasty (China). Ögedei's general Subutai captured the capital of Emperor Wanyan Shouxu in the siege of Kaifeng in 1232. The Jin dynasty collapsed in 1234 when the Mongols captured Caizhou, the town where Wanyan Shouxu had fled. In 1234, three armies commanded by Ögedei's sons Kochu and Koten, as well as the Tangut general Chagan, invaded southern China. With the assistance of the Song dynasty, the Mongols finished off the Jin in 1234.
Many Han Chinese and Khitan defected to the Mongols to fight against the Jin. Two Han Chinese leaders, Shi Tianze, Liu Heima (劉黑馬, Liu Ni), and the Khitan Xiao Zhala defected and commanded the 3 Tumens in the Mongol army. Liu Heima and Shi Tianze served Ogödei Khan. Liu Heima and Shi Tianxiang led armies against Western Xia for the Mongols. There were 4 Han Tumens and 3 Khitan Tumens, with each Tumen consisting of 10,000 troops.
Shi Tianze was a Han Chinese who lived in the Jin dynasty (1115–1234). Interethnic marriage between Han and Jurchen became common at this time. His father was Shi Bingzhi (史秉直, Shih Ping-chih). Shi Bingzhi was married to a Jurchen woman (surname Na-ho) and a Han Chinese woman (surname Chang), it is unknown which of them was Shi Tianze's mother. Shi Tianze was married to two Jurchen women, a Han Chinese woman, and a Korean woman, and his son Shi Gang was born to one of his Jurchen wives.
The Mongols at war
His Jurchen wive's surnames were Mo-nien and Na-ho, his Korean wife's surname was Li, and his Han Chinese wife's surname was Shi. Shi Tianze defected to the Mongol Empire's forces upon their invasion of the Jin dynasty. His son Shi Gang married a Kerait woman, the Kerait were Mongolified Turkic people and considered as part of the "Mongol nation".
The Yuan dynasty created a "Han Army" 漢軍 out of defected Jin troops and army of defected Song troops called the "Newly Submitted Army" 新附軍.
In the West, Ögedei's general Chormaqan destroyed Jalal ad-Din Mingburnu, the last shah of the Khwarizmian Empire. The small kingdoms in Southern Persia voluntarily accepted Mongol supremacy. In East Asia, there were a number of Mongolian campaigns into Goryeo Korea, but Ögedei's attempt to annex the Korean Peninsula met with little success. The king of Goryeo, Gojong, surrendered but later revolted and massacred Mongol darughachis (overseers); he then moved his imperial court from Gaeseong to Ganghwa Island. As the empire grew, Ögedei established a Mongol capital at Karakorum in northwestern Mongolia.
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