How was Hyderabad merged with India …

Operation Polo was the code name of the Hyderabad "police action" in September 1948, by the then newly independent Dominion of India against Hyderabad State. It was a military operation in which the Indian Armed Forces invaded the Nizam-ruled princely state, annexing it into the Indian Union. At the time of Partition in 1947, the princely states of India, who in principle had self-government within their own territories, were subject to subsidiary alliances with the British, giving them control of their external relations. In the Indian Independence Act 1947 the British abandoned all such alliances, leaving the states with the option of opting for full independence. However, by 1948 almost all had acceded to either India or Pakistan. One major exception was that of the wealthiest and most powerful principality, Hyderabad, where the Nizam, Mir Sir Osman Ali Khan, Asaf Jah VII, a Muslim ruler who presided over a largely Hindu population, chose independence and hoped to maintain this with an irregular army recruited from the Muslim aristocracy, known as the Razakars. The Nizam was also beset by the Telangana uprising, which he was unable to subjugate.