Spread over most of the Deccan Plateau, the Hyderabad State was established by Nizam-ul-Mulk Asaf Jah in 1724 after the end of the Mughal Empire. Under the rule of Mir Usman Ali, the Hyderabad state was very prosperous and had its own army, railway and airline network, postal system and radio network. In 1947, the then Indian Home Minister Sardar Patel requested the Nizam to join India, but he refused and instead declared Hyderabad an independent nation on 15th August 1947, the day Indian received Independence. The Indian Government then offered Hyderabad a Standstill Agreement, which assured the state that no military action would be taken against it. Unlike the other princely states which acceded to either India or Pakistan, Hyderabad only promised India that it would not join Pakistan. In June 1948, Lord Mountbatten proposed the Heads of Agreement deal which gave Hyderabad the status of an autonomous dominion nation under India. The deal was signed by India, but the Nizam refused to sign this saying that he either wanted complete independence or the status of a dominion under the British Commonwealth of Nations. While these negotiations were being carried out, communal riots between Hindus and Muslims had broken out in Hyderabad. The state was also busy arming itself and was receiving arms from Pakistan and the Portuguese administration in Goa.

As soon as the Indian Government received information that Hyderabad was arming itself and planning to ally with Pakistan, Sardar Patel described the idea of an Independent Hyderabad as “an ulcer in the heart of India which needed to be removed surgically”. This was when talks between India and Hyderabad broke down and India decided to annex Hyderabad under “Operation Polo” and “Operation Caterpillar”, or more commonly referred to as “Police Action”. The battle between India and Hyderabad began on 13th September 1948 and ended on 18th September 1948 after which the Nizam’s army surrendered to the Indian Army and Hyderabad became a part of the Union of India. It is estimated that 32 were killed and 97 injured on the Indian side and 490 killed and 122 wounded on the Hyderabadi side. Subsequentky Hyderabad state was merged with Andhra state to form Andhra Pradesh in 1956.

 

Reference:

http://www.mapsofindia.com/on-this-day/18th-september-1948-operation-polo-is-terminated-after-the-indian-army-accepts-the-surrender-of-the-nizam-of-hyderabads-army

http://indiatoday.intoday.in/story/hyderabad-indian-army-telangana-police-action-independent-india/1/309167.html