The History of Korea District dates back to 1600. According to Dalton, Balands were the actual rulers of Korea who had their capital in Sidhi. There are still remnants of the ruins of the works accomplished by them. However, later a united force of the Kol Raja and Gonnd Zamindars overthrew the Baland rulers from Korea. The Kols also known as Konch Kols ruled for Eleven Generations. According to one view the Kols had their Capital at Koreagarh while others suggest that it was village Bachra near Podi.

In early 17th century, two cousins of the Agnikul Chauhan Raja of Mainpuri, Dalthmban Sahi and Dharamal Sahi were returning after pilgrimage to Jagannath Puri along with a small force. While returning they stopped at Bishrampur, the Capital of Surguja State. During their stay some rebel sardars of the State attacked the place. The king was away hence the queen sent the traditional Rakhi to the Chauhan brothers asking for help. The brothers came to her rescue and drove away the bagi sardars. After the Maharaja returned, he thanked the Chauhan brothers for their act and offered them the Jagirdari of the area on the Eastern part of the State known as Jhilmili. A part of Jhilmili Area was under control of Baland Rajas.

The Chauhan brothers settled at Kaskela village on the banks of the River Rehar. They drove away the Baland from the area. They paid an Annual Tribute to the Surguja State. The title of Bhaiya was bestowed upon the family by Maharaja Amar Singh since after the tying of the Rakhi, the brothers had become bhaiyas of Rani. This was later known as Bhaiyathan. The younger brother Dharamal Sahi stayed with his brother at Kaskela but later decided to build his own kingdom. He gathered a force and moved westward beyond the boundary of Surguja District into Korea State, which was ruled by a Kol Raja.

He defeated him in a battle and took over the Kingdom of Korea. Dharamal Sahi drove away Balands from the Northen territory of Korea State. Dharamal Sahi had three sons Deoraj Sahi, Adhorai Deo and Raghorai Deo. On the death of Dharamal Sahi his eldest son Deoraj Sahi ascended to the throne. As the eldest son had no child his younger brother`s son Raja Narsingh Deo became the next king. He was succeeded by his son Raja Jeet Rai Deo. He was followed by his son Raja Sagar Sahi Deo. On his death, his son Raja Afhar Sahi Deo ascended the throne. His son Raja Jahan Sahi Deo succeeded him. He was succeeded by his son Raja Sawal Sahi Deo. On his death his son Raja Gajraj Singh Deo became the King. He was issueless and was succeeded by his nephew Raja Garib Singh son of Lal Dilip Singh Deo. Raja Garib Singh`s younger brother Lal Man Singh was given a Jagir, which was named Changbhakar. He became the Jagirdar of Changbhakar, which had its capital at Bharatpr. Raja Garib Singh was born in 1745 at Nagar. Near about 1765 the forces of Bhosle`s of Nagpur attacked Nagar and forced Raja Garib Singh to pay Chauth. He paid the Chauth for some time and then stopped paying the same to the Marathas. He moved his Capital to Rajauli and then to Sonhat. The capital was moved to the interior for fear of Maratha attacks.

In 1797 the Marathas under Subedar Gulab Khan attacked Sonhat and forced Raja Garib Singh to pay Chauth. Gulab Khan who was the Maratha Subedar came with 200 soldiers and ravaged the countryside. On their return journey at Latma Village, the forces of Patna Zamindar attacked them. The Marathas beat a hasty retreat into Surguja State. After the defeat of Modeji Bhosle of Nagpur by the British East India Company, the Chhattisgarh States came under the suzerainty of the East India Company. In the Kabuliat executed on 24th December 1819 by Garib Singh, it was decided that Korea State will pay an annual tribute of Rs. 400. Raja Garib Singh was succeeded by Raja Amol Singh but he proved to a weak Raja. Hence the State was virtually ruled by his wife Rani Kadam Kunwar. After the death of Amol Singh in 1864 his son Raja Pran Singh became the next king.

As Pran Singh Deo was issueless after his death Raja Sheomangal Singh Deo became the next king. Raja Sheomangal Singh Deo moved his capital from Sonhat to Baikunthpur in the year 1900. He also constructed the two tanks and a temple, which are near the new palace. After his death his eldest son, Raja Ramanuj Pratap Sing Deo became the king. As he was a child the State was put under court of wards with Gore Lal Pathak Superintendent of Korea State. He continued till 1916. Pandit Gangadin Shukla took over from him and continued till 1918. He was followed by RaghubirPrasad Verma. Finally In January 1925, Raja Ramanuj Pratap Singh Deo was invested with full ruling with full ruling powers and continued till the merge the Korea State in to independent India. Raja Ramanuj Pratap Singh Deo represented the ruling Chief, in the second Round Table Conference held in London in 1931. Under his rule the income of the Korea State rose from 2.25 lakhs to 44 lakhs in 1947-1948, and there was a reserve of over rupees one crore when the State was merged with Central Provinces and Berar. In this duration so many works were done. In 1928, construction of Bijuri - Chirimiri Railway Line started and completed on 1931. In 1928 Chirimiri Colliery opened by Bansi lal Abirchand. In 1928 Khurasia collery is started. In 1929, Jhagarakhand Colliery is opened. In 1930 railway communication to Manendragarh is started. In 1935 Ramanuj High School opened. On 15th December 1947, Raja Ramanuj Pratarp Singh Deo signed the merger agreement by which the state was merged to the Central Provinces and Berar and finally 1st January 1948, State is merged with Central Provinces and Berar.