List of Important Wars and Battles in Indian History S.N. Name of the Battle Year Battle between Won by Significance 1 Battle of Hydaspas 326 B.C. Alaxender and Porus Alaxender defeated king Porus Impressed by the bravery of Porus, he allowed to retian the kingship of Porus 2 Kalinga War 261 B.C. Ashoka and Raja