Since the 19th century the princely states and the tributary states of Orissa and Chhota Nagpur were not part of Bengal, but British relations with them were managed by its government through the Bengal Presidency.
The Eastern States Agency was created on 1 April 1933. This agency dealt with forty-two princely states in eastern India, located in the present-day Indian states of Chhattisgarh, Jharkhand, Odisha, West Bengal and Tripura. Before the creation of the Eastern States Agency in 1933, twenty-three native states of the former Orissa Tributary States and Chhota Nagpur States were under the suzerainty of the British provinces of Bihar and Orissa and sixteen were under that of the Central Provinces.
The Agent reported to the Governor General of India and two Political Agents under his supervision were posted at Sambalpur and Raipur.
Cooch Behar and Tripura were transferred from Bengal Province to the Eastern States Agency on 1 November 1936.
On 1 December 1944, the status of this agency was raised to that of a first class residency. These states were grouped into three political agencies, under the "Resident" in Calcutta. The headquarters of the Orissa States Agency was at Sambalpur, the headquarters of the Chhattisgarh States Agency was at Raipur and the headquarters of the Bengal States Agency was at Calcutta. After the withdrawal of the British from India in 1947, the states acceded to the new Union of India and some of the states formed the Eastern States Union, an organisation that failed. Later they were integrated into the Indian states of Madhya Pradesh, Bihar, West Bengal and Orissa. The eastern portion of Madhya Pradesh and the southern portion of Bihar became the states of Chhattisgarh and Jharkhand, respectively, in November 2000.
Link to the Map of Eastern States Agency