After the overthrow of the Mongol Yuan dynasty by the Ming dynasty in 1368, Manchuria remained under control of the Mongols of the Northern Yuan dynasty based in Mongolia. Naghachu, a former Yuan official and a Uriankhai general of the Northern Yuan dynasty, won hegemony over the Mongol tribes in Manchuria (Liaoyang province of the former Yuan dynasty). He grew strong in the northeast, with forces large enough (numbering hundreds of thousands) to threaten invasion of the newly founded Ming dynasty in order to restore the Mongols to power in China. The Ming decided to defeat him instead of waiting for the Mongols to attack. In 1387 the Ming sent a military campaign to attack Naghachu, which concluded with the surrender of Naghachu and Ming conquest of Manchuria.