At the height of their empire, they controlled most of the Ganges valley and an arc that extended through Afghanistan and Central Asia into Xinjiang. Once there, they displaced the Greco-Bactrian kingdom and expanded over the Hindu Kush mountains into today’s India and Pakistan. The Kushan Empire (135 B.C.E.-375 C.E.) was founded in the Bactria region of northern Afghanistan by Yuezhi nomads who migrated there from Xinjiang due to Han Dynasty campaigns. Despite Chanakya’s book, the empire depended less on institutions than on able rulers, the lack of which doomed it and led to increasing local rule. However, the empire’s fragmentation reveals the problems of actually maintaining an empire in a region as diverse as South Asia. Some historians have argued that the elevation of Buddhism was responsible for this as it is not as compatible with running a state as Hinduism. The Maurya Empire collapsed not too long after Ashoka's death in 232 B.C.E. ( Recommended: China's 3 Most Powerful Dynasties) This grandson, Ashoka, is famous for having embraced Buddhism due to remorse after his bloody conquest of Kalinga (today’s Orissa) around 260 B.C.E. By the time of Chandragupta’s grandson’s reign, the empire included most of South Asia except the southernmost parts of it. After a treaty with Alexander’s generals, the empire acquired territory in Afghanistan and Iran. Many of its policies were set out by Chanakya, Chandragupta’s minister, who wrote a book advocating a strong, centralized, authoritarian state, The Arthashastra. The empire was initially very successful both internally and in terms of foreign policy.

Feudal kingdoms became the norm