 Sonepur was declared as a Tributary state under British occupation.But with the defeat of the Marathas in the third Anglo-Maratha war on 1817, Raja Prithvi Singh was released and sonepur permanently came under British protection.His successor Raja Niladhar Sing Deo (AD 1855-1891) was very much loyal to British Government and rendered all possible help during sepoy mutiny, rebellion of Surendra Sai and the Kondh rebellion of Chakra Bisoi and was rewarded with the title 'Raja Bahadur' for these help.