Conquest of Kalinga (Modern Odisha) is mentioned in Ashokan Inscriptions. Ashoka's coronation took place in 269-68 BC and eight years after his coronation, he campaigned for Kalinga and Conquest of Kalinga took place in 9th year of Ashoka's reign i.e. 260BCE.The Kalinga war was a horrifying event. It mentions that hundred and fifty thousand people were displaced, hundred thousand people were killed .The vivid description of Kalinga war is given in 13th Rock Edict.