Operation Polo was the code name for the police action that integrated Hyderabad into the Indian Union. It was a military operation conducted by the Indian Armed Forces in September 1948 to annex the princely state of Hyderabad, which had decided to remain independent after India's independence from British rule in 1947. The operation lasted for just five days and resulted in the complete integration of Hyderabad into the Indian Union.

Background:
- Hyderabad, ruled by the Nizams, was the largest princely state in India, with a predominantly Hindu population but a Muslim ruler.
- The Nizam, Mir Osman Ali Khan, initially wanted Hyderabad to remain independent but later expressed his desire to join Pakistan.
- The Indian government, led by Prime Minister Jawaharlal Nehru, was determined to integrate Hyderabad into the Indian Union.

Events:
- The Indian government attempted negotiations with the Nizam to peacefully integrate Hyderabad, but the discussions failed.
- As a result, the Indian government decided to launch a military operation to annex Hyderabad and bring it under Indian control.
- On September 13, 1948, Indian forces commenced Operation Polo by launching air strikes on key targets in Hyderabad.
- The Indian Army, supported by the Indian Air Force, quickly advanced and captured major cities and towns of Hyderabad.
- The Nizam's forces, known as the Razakars, put up some resistance but were eventually defeated.
- The operation concluded on September 18, 1948, with the surrender of the Nizam's forces and the complete integration of Hyderabad into the Indian Union.

Significance:
- Operation Polo was a significant military and political success for the Indian government.
- It ensured the integration of Hyderabad, a strategically important region, into the Indian Union.
- The operation also brought an end to the rule of the Nizams and established democratic governance in Hyderabad.
- The successful execution of Operation Polo demonstrated the strength and resolve of the Indian Armed Forces and solidified India's position as a united nation.

Conclusion:
Operation Polo, also known as the police action to integrate Hyderabad into the Indian Union, was a military operation that resulted in the successful annexation of Hyderabad. It was a significant event in Indian history, marking the integration of a major princely state into the newly independent nation.