The Kingdom of Burundi, or Urundi, in the Great Lakes region was a polity ruled by a traditional monarch with several princes beneath him; succession struggles were common. The king, known as the ''mwami'' (translated as ruler) headed a princely aristocracy (''ganwa'') which owned most of the land and required a tribute, or tax, from local farmers (mainly Hutu) and herders (mainly Tutsi). The Kingdom of Burundi was characterised by a hierarchical political authority and tributary economic exchange.