This state has seen a vigorous agitation from the inhabitants in the name of Praja Andolon as seen in other states also. The Amco-Simco violence is considered as one of the most important one. Though, it ended with a blind firing that claimed loss of 32 tribal lives, but opened the eyes for others.
It is alleged that people didn’t give any revenue to the Royal Court and disobey the rules of the state. The King Bir Udit Pratap Sekhar Deo became afraid of this movement and stays out of the state at his maternal uncle’s state i.e., Visakha Patnam. He considered Vizag as safer than Gangpur. So the estate at Gangpur lost its importance gradually.
After India’s independence, a movement for merger of princely states in India was started by the Union Home ministry. To protect self interest of the royalty in Odisha Maharaja of Patna made an ally with some states in the eastern region and put demands before Sardar Ballav Bhai Patel the then Home Minister of Indian Govt.
This charter was consisted of four major charters. First of all they demanded Odisha Legislature should be of bicameral and the Upper House should bear the rulers of the 26 princely states and their heirs as permanent members. The second important point was regarding fixed and guaranteed Privy Purse, protection of private properties and personal privileges. Sardar Ballav Bhai Patel and his Secretary VP Menon considered all these demands and assured them for a dignified life by passing the demands to the State Govt to make them fulfilled.
After a long discussion at Cuttack the ruler of Gangpur signed the merger agreement with Union of India at Cuttack and let the State to be part of the Odisha State in December 14, 1947. From 1st of January this has been executed and Gangpur is considered as an important District of Odisha with the modern name Sundargarh as its Head Quarter.