The history of Odisha dates back to antiquity, its most famous old names being Kalinga, Utkal and Odra, when its boundary extended far beyond the present one. By the time of the Mahabharata Kalinga, Utkal and Odra had entered into Aryan polity as powerful kingdoms. Frequent reference is made to Kalinga in the Mahabharata and infrequent references to Odra and Utkal. By the time of Mahavir and Buddha, the Kalinga-Utkal region on the entire east coast of India acquired recognition and fame.

The political history of Odisha opens with the rule of Nanda, Emperor of Magadha. The Hathigumpha inscription of Emperor Kharavela at Udaygiri refers to a Nanda king twice. When Chandragupta Maurya succeeded to the throne of Nanda, Kalinga did not form part of his empire. Asoka's invasion of Kalinga was an epoch-making event of ancient times of far-reaching consequences. The battle was described by Asoka himself in his thirteenth Rock Edict which records. One hundred and fifty thousand men were carried away captive from that country, as many as one hundred thousand were killed there in action and many times that number perished. Kalinga was conquered but the conquest changed the heart of the conqueror. This change in Asoka changed the course of religion and cultural history not only of India but also of the whole of Asia. The next great epoch of Odisha history was the time of Kharavela who ruled in the first half of the second century B.C. He defeated the Satakarni in the west, the Musikas on the bank of the Krishna as also the Rashtrikas and the Bhojakas, the rulers of Rajagriha and King Brihaspati Mitra of Magadha. In the thirteenth year of his rule he retired to Khandagiri near Bhubaneswar. He was a Jain.

The history of Odisha for several centuries after Kharavela is dark. From Hiuen Tsang's account it is evident that Harsha Siladitya's political sway extended to Odisha. Ptolemy, the famous Greek Geographer of the 2nd century A. D., testified to the existence of flourishing trade marts on the Odisha coast. In the 8th century A. D. Odisha's overseas activities were at their peak when the Sailendra Empire in present day Malayasia was estabilshed. According to Arab sources, the empire extended its power even into Cambodia and Assam. The prosperity of the Sailendra Empire continued through the 10th century A. D.

From the 8th to the 10th centuries A. D. the Bhauma-Kara dynasty ruled over Utkal. Odia language was just beginning to take shape during this age. This Bhauma-Kara were followed by the Somas and the Kesharis. The famous Lingaraj Temple at Bhubaneswar was built by Yajati Keshari and completed by his successors.

By the end of the 12th Century A. D. Anantavarma Chodagangadeva (1078-1191) of the Ganga dynasty is credited with having ruled over the region extending from the Ganga to the Godavari. He shifted his capital from Kalinganagar in Parlakhemundi to Cuttack. Vaishnavism received royal patronage and Vaishnavite temples were built at Mukhlingam, Shrikurmam, Simachalam and Puri. The temple at Puri was completed by Anangabhimadeva. In the 13th century the Ganga empire had the power to thwart a Muslim invasion.

In the 13th century when Hindu architecture in the north faced its worst days of ravage and destruction, Odisha architecture reached its zenith with the construction of the famous Sun Temple of Knar by Narasimhadeva I (A. D. 1238-1264). It is recognised as the crowning glory of Hindu architecture. Then came the Surya dynasty. The first Surya King, Gajapati Kapilendradeva (1435-1466) defeated the Muslim ruler of Bengal, the Hindu ruler of Vijayanagar and Kanchi, and the Bahamani Sultan. Kapilendra in fact himself advanced to Bidar, the capital of the Bahamani Empire. His empire extended from the Ganga in the north to the Kaveri in the South. His grandson, Prataparudradeva, became a devout disciple and with his death Surya rule declined. Mukundadeva the last independent king of Odisha, was killed in 1568 while fighting Afghans of Bengal. With his death Odisha lost its independence and thus became almost the last Hindu Kingdom of India to fall to the Muslims.

The Moghuls ruled Odisha for a little over a century. During Aurangzeb's rule, however, a revolt was started under the leadership of Raja Krishna Chandra Bhanj of Mayurbhanj, but it was suppressed, though with great difficulty. After Aurangzeb's death, when the Moghul Empire declined, Odisha passed under the rule of the independent Nawabs of Bengal. In 1741 the Bhonsala Raja of Nagpur invaded Odisha under the leadership of Bhaskar Ram (Bhaskar Pandit). Alivardi Khan, the Nawab of Bengal, was compelled to code Odisha to the Marathas whose rule lasted until the British conquered it in 1803.

Within two decades of Vasco-da-Gamas discovery of the sea-route to India the Portuguese had established a flourishing trade mart at Pipli, at the mouth of the Subarnarekha. The English had established trade settlements at Hariharpur and Balasore by 1633. In subsequent years, the Dutch, the Danes and the French appeared at Balasore and established their respective footholds. In 1757 when the Battle of Plassey was fought and won, the legal title of Nawab of Bengal, Bihar and Odisha passed on to the English. In 1765, Shah Alam granted the East India Company the Dewani of Bengal, Bihar and Odisha. But this Odisha was only a small territory to the north of the Subarnarekha. Lord Wellesley (1798-1805) asked the Bhonsala Raja of Nagpur to enter into a Subsidiary Alliance, but the Raja refused. The Anglo-Maratha war resulted in the British conquest of Odisha in 1803. Owing to misrule of the British, the Paika Rebellion was started under the leadership of Bakshi Jagabandhu Bidyadhar, the millitary chief of the Raja of Khurda. In April 1817 Puri fell to him and the British retreated to Cuttack. In the end, however, the rebellion was crushed. In 1857 Sambalpur played a leading role in the great Indian revolt. The worst evil of the British administration was witnessed in 1865-66 during the Na Anka famine in which more than ten lakhs of people, comprising about a quarter of Odisha's population, died of starvation.

The social reformers of Odisha like Fakir Mohan Senapati, Bhagban Chandra Das, Radhanath Ray, Madhusudan Rao and Madhusudan Das, shaped the destiny of Odisha in various significant ways. During the First World War a forceful movement was organised and led by Pandit Gopabandhu Das. As a result, Odisha was separated from Bengal, Madras and Central Provinces. It came into existence on 1st April, 1936. Soon after this, the Gadajat Revolt of the princes of the States was suppressed in 1938. Odisha took full part in the 1942 movement when more than 3,000 persons were thrown behind the bars and about 100 persons were killed as a result of machine-gun firing. After the attainment of Independence the princely States merged with the major unit in 1948 and the new State of Odisha was formed.

An administrative reorganisation of the State was taken in hand and thirteen districts were formed. Out of the former princely States the districts of Mayurbhanj, Sundargarh, Keonjhar, Dhenkanal, Phulbani, Bolangir and Kalahandi were carved out.

As a result of the work of the States Reorganisation Commission, the princely States of Saraikela and Kharasuan were merged with Bihar. Earlier, they were parts of the Mayurbhanj district.