Mongol invasions of India invasions might give a better indication of the numbers involved, as these commanders probably led tumens, units nominally of 10,000 men. These invasions were led by either various descendants of Genghis Khan or by Mongol divisional commanders; the size of such armies was always between 10,000-30,000 cavalry although the chroniclers of Delhi exaggerated the number to 100,000-200,000 cavalry. After civil war broke out in the Mongol Empire in the 1260s, the Chagatai Khanate controlled Central Asia and its leader since the 1280s was Duwa Khan who was second in command of Kaidu Khan. Duwa was active in Afghanistan, and attempted
Mongol conquest of the Song dynasty expelled his opponents like Wen Tianxiang and Li Fu. Because the financial revenue of the late Southern Song state was very low, Jia Sidao tried to reform the regulations for the merchandise of lands with his state field law. Gunpowder weapons like the "t'u huo ch'iang" were deployed by the Chinese against the Mongol forces, which fired bullets from bamboo tubes. After Kublai was elected Great Khan of the Mongols in 1260 he was eventually able to conquer the Song to the south, but at great cost. From 1260 to 1264, he faced civil insurrection within the Mongol side led