Can anyone tell me the extent of Ashoka's empire?
Ashoka's empire encompassed almost the whole of the Indian sub-continent. Geographically, it stretched from present day Afghanistan and Pakistan to Bangladesh. Alexander the Great had conquered a great deal of India; but when he withdrew, this left a power vacuum that was filled by Ashoka's grandfather, Changdragupta Maurya. This was the beginning of the Mauryan dynasty. After his death, Ashoka conquered the remainder of the sub-continent in a campaign that was quite bloody. The bloodshed caused him to dedicate himself to Buddhism.
Ashoka’s empire crumbled almost immediately after his death in 232 B.C.E., largely due to economic difficulties. The cost of maintaining an army (which was largely inefficient) outpaced revenue; and subsequent emperors attempted to compensate for the loss by debasing the currency (reducing the gold or silver in the coin without reducing its face value.) The Mauryan Empire disintegrated c. 185 B.C.E., after which local rulers ruled a series of localized kingdoms.