Hong Taiji
In 1636, Hong Taiji invaded Joseon Korea, as the latter did not accept that Hong Taiji had become emperor and refused to assist in operations against the Ming. With the Joseon dynasty surrendered in 1637, Hong Taiji succeeded in making them cut off relations with the Ming dynasty and force them to submit as tributary state of the Qing dynasty. Also during this period, Hong Taiji took over Inner Mongolia in three major wars, each of them victorious. From 1636 until 1644, he sent 4 major expeditions into the Amur region. In 1640 he completed the conquest of the Evenks, when he defeated and captured their leader Bombogor. By 1644, the entire region was under his control.