<Li> Hyderabad (Hindu majority state with a Muslim nizam)--Patel ordered the Indian army to depose the government of the Nizam after the failure of negotiations, which was done between 13--17 September 1948 . It was incorporated as a state of India the next year . </Li> <Li> The area of Kashmir (Muslim majority state with a Hindu king) in the far north of the subcontinent quickly became a source of controversy that erupted into the First Indo - Pakistani War which lasted from 1947 to 1949 . Eventually a United Nations - overseen ceasefire was agreed that left India in control of two - thirds of the contested region . Jawaharlal Nehru initially agreed to Mountbatten's proposal that a plebiscite be held in the entire state as soon as hostilities ceased, and a UN-sponsored cease - fire was agreed to by both parties on 1 Jan. 1949 . No statewide plebiscite was held, however, for in 1954, after Pakistan began to receive arms from the United States, Nehru withdrew his support . The Indian Constitution came into force in Kashmir on 26 January 1950 with special clauses for the state . </Li> <P> The Constituent Assembly adopted the Constitution of India, drafted by a committee headed by Dr. B.R. Ambedkar, on 26 November 1949 . India became a sovereign democratic republic after its constitution came into effect on 26 January 1950 . Dr. Rajendra Prasad became the first President of India . The three words' socialist',' secular' and' integrity' were added later with the 42nd Constitution Amendment 1976 . </P> <P> The Indo - Pakistani War of 1947--1948 was fought between India and Pakistan over the princely state of Kashmir and Jammu from 1947 to 1948 . It was the first of four Indo - Pakistan Wars fought between the two newly independent nations . Pakistan precipitated the war a few weeks after independence by launching tribal lashkar (militia) from Waziristan, in an effort to secure Kashmir, the future of which hung in the balance . The inconclusive result of the war still affects the geopolitics of both countries . </P>

When did the constitution of india came into force