The country now called India was once divided into 56 kingdoms. The borders of the kingdom are often marked by rivers, sometimes even forests and mountain ranges also forms the borders between two neighboring kingdoms.
A main city in the kingdom will act like a capital with the king and the courtsmen reside to administer the kingdom. Tax was collected by the officers appointed by the king from these villages and towns. What the king offered in return to these villages and towns was protection from the attack of other kings and robber tribes, as well as from invading foreign nomadic tribes. The king also enforced code and order in his kingdom by punishing the guilty.
There was no border security for a kingdom and border disputes were very rare. One king might conduct a military campaign (often designated as Digvijaya meaning victory over all the directions) and defeat another king in a battle, lasting for a day. The defeated king would acknowledge the supremacy of the victorious king. The defeated king might sometimes be asked to give a tribute to the victorious king. Such tribute would be collected only once, not on a periodic basis. The defeated king, in most cases, would be free to rule his own kingdom, without maintaining any contact with the victorious king.
Kingdoms of Ancient India: