 The Indian Independence Act 1947 ( 10 & 11 Geo 6 c . 30 ) passed by the Parliament of the United Kingdom divided British India into the two new independent dominions ; the Dominion of India ( later to become the Republic of India ) and the Dominion of Pakistan ( later to become the Islamic Republic of Pakistan ) . The act provided a mechanism for division of the Bengal and Punjab provinces between the two nations ( see partition of India ) , establishment of the office of the Governor @-@ General , conferral of complete legislative authority upon the respective Constituent Assemblies , and division of joint property between the two new countries . On 14 August 1947 , the new Dominion of Pakistan became independent and Muhammad Ali Jinnah was sworn in as its first governor general in Karachi . Independence was marked with widespread celebration , but the atmosphere remained heated as communal riots marked the independence of Pakistan in 1947 . The act later received royal assent on 18 July 1947 . 
