Maurya Empire
Historians theorise that the organisation of the Empire was in line with the extensive bureaucracy described by Chanakya in the Arthashastra: a sophisticated civil service governed everything from municipal hygiene to international trade. The expansion and defense of the empire was made possible by what appears to have been one of the largest armies in the world during the Iron Age. According to Megasthenes, the empire wielded a military of 600,000 infantry, 30,000 cavalry, 8,000 chariots and 9,000 war elephants besides followers and attendants. A vast espionage system collected intelligence for both internal and external security purposes. Having renounced offensive warfare and expansionism, Ashoka nevertheless continued to maintain this large army, to protect the Empire and instil stability and peace across West and South Asia..Even though large parts were under the control of  Mauryan empire the spread of information and imperial message was limited since many parts were inaccessible and were situated far away from capital of empire.