Explanation:

During 2nd millennium BCE the use of Copper tools spread in Chota Nagpur Plateau and these find complex are known as the Copper Hoard Culture. In Kabra-Kala mound at the confluence of Son and North Koel rivers in Palamu district various antiquities and art objects have found which are from Neolithic to the medieval period and the pot-sherds of Redware, black and red ware, black ware, black slipped ware and NBP ware are from Chalcolithic to the late medieval period. Several iron slags, microliths, and potsherds have been discovered from Singhbhum district which are from 1400 BCE according to carbon dating age. The region was ruled by many empires and dynasties including Maurya, Gupta, Pala and Nagvanshi during ancient period.