Odisha, formerly known as Orissa, is an Indian state on the subcontinent's east coast, by the Bay of Bengal. It is surrounded by the Indian states of West Bengal to the north-east and in the east, Jharkhand to the north, Chhattisgarh to the west and north-west and Andhra Pradesh to the south. It is the modern name of the ancient kingdom of Kalinga, which was invaded by the Mauryan Emperor Ashoka in 261 BCE. The modern state of Orissa was established on 1 April 1936, as a province in British India and consisted predominantly of Oriya speakers. 1 April is therefore celebrated as Utkala Dibasa (foundation day of Odisha). The region is also known as Utkala when mentioned in India's national anthem, "Jana Gana Mana". Cuttack remained the capital of the state for over eight centuries until 13 April 1948 when Bhubaneswar was officially declared as the new state capital, a position it still holds.
Odisha is the 9th largest state by area in India, and the 11th largest by population. Oriya (officially spelled Odia) is the official and most widely spoken language, spoken by three quarters of the population. Odisha has a relatively unindented coastline (about 480 km long) and lacked good ports, except for the deepwater facility at Paradip, until the recent launch of the Dhamra Port. The narrow, level coastal strip, including the Mahanadi river delta, supports the bulk of the population.
Since prehistoric days the land of Odisha has been inhabited by various people. The earliest settlers of Odisha were primitive hill tribes. Although prehistoric communities cannot be identified, it is well known that Odisha had been inhabited by tribes like Saora or Sabar from the Mahabharata days. Saora in the hills, and the Sahara and Sabar of the plains continue to be an important tribe distributed almost all over Odisha. Most of the tribal people have been influenced by Hindus and have adopted Hindu manners, customs and rituals. Bonda Parajas of Koraput district are the best example of these tribes. Several pre-historic sites have been excavated in Odisha since the arrival of Britishers. Kaliakata of Angul, Kuchai and Kuliana of Mayurbhanj, Vikramkhol near Jharsuguda, Gudahandi and Yogimath of Kalahandi, Ushakothi of Sambalpur, Similikhol near Bargarh etc.
Odisha has a history spanning a period of over 5,000 years. Before Kalinga it was named as Udra or "Odra Desa". The Ancient Odra desa or Ordesa was limited to the valley of Mahanadi and to the lower course of Subarnarekha River. It comprised the whole of the present districts of Cuttack and Sambalpur and a portion of Midnapur. Bounded on the west by Gondwana, on the north by the wild hill states of Jaspur and Singhbhum, on the east by the sea and on the South by Ganjam, Odisha has a legendary history. The name Oriya originated from Odra or Udra tribes that inhabited the central coastal belt (Khordha District and Nayagarh District) of modern Odisha. Odisha has also been the home of the Kalinga, Utkal, Mahakantara/Kantara and Kosal that played a particularly prominent role in the region's history, and one of the earliest references to the ancient Kalingas appears in the writings of Vedic chroniclers. In the 6th century BCE, Vedic Sutrakara Baudhayana mentions Kalinga as being beyond the Vedic fold, indicating that Brahminical influences had not yet touched the land. Unlike some other parts of India, tribal customs and traditions played a significant role in shaping political structures and cultural practices right up to the 15th century, when Brahminical influences triumphed over competing traditions and caste differentiation began to inhibit social mobility and erode what had survived of the ancient republican tradition.
Tel river civilisation put light towards a great civilisation existing in Kalahandi, Balangir, Koraput (KBK) region in the past that is recently getting explored. The discovered archaeological wealth of Tel Valley suggest a well civilised, urbanised, cultured people inhabited on this land mass around 2000 years ago and Asurgarh was its capital. Kalahandi along with Koraput and Bastar was part of Kantara referred in Ramayana and Mahabharata. In 4th century BCE, this region was known as Indravana from where precious gem-stones and diamond were collected for the imperial Maurya treasury. During the period of Maurya emperor Ashoka, Kalahandi along with Koraput and Bastar region was called Atavi Land. This land was unconquered as per Ashokan record. In the beginning of the Christian era probably it was known as Mahavana. In the 4th Century CE, Vyaghraraja was ruling over Mahakantara comprising Kalahandi, undivided Koraput and Bastar region. Asurgarh was capital of Mahakantara.
On the other hand in the 3rd century BCE, in the eastern part of Odisha, Kalinga flourished as a powerful empire under the Jaina emperor, Kharavela. He ruled all the way down south to include parts of the Tamil country. He built the superb monastic caves at Udayagiri and Khandagiri Caves. Subsequently, the region was ruled under various monarchs, such as Samudragupta and Shashanka. It also was a part of Harsha's empire. In 795 CE, the king Jajati Kesari I of Kesari or Soma dynasty of Kosala united Kosala and Utkala into a single empire. He is also supposed to have built the first Jagannath Temple at Puri, although the current structure of the temple is entirely different and was built by Kings Choda Gangadeva and Ananga Bhimadeva of the Eastern Ganga Dynasty in the 12th century. The famous Lingaraja temple in Bhubaneshwar was started by Keshari dynasty king Jajati Keshari III and completed by his son Lalatendu Keshari in the 10th century. King Narasimha Dev is reputed to have built the magnificent Konark Sun Temple. Although now largely in ruins, the temple may have once rivalled the Taj Mahal in splendor. Orissa was conquered by Raja Raja Chola I and Rajendra Chola I of the Chola dynasty in the early 11th century.
Odisha resisted several Muslim attacks until 1568, when was conqurered by Sultanate of Bengal. The Mughals conquered Coastal Odisha in 1576. The last Hindu Emperor of Odisha, Gajapati Mukunda Deva, was defeated and was killed in the battle of Gohiratikiri. The coastal plain of Odisha from Medinipur to Rajahmundry came under Mughal rule, which was broadly divided into six parts as Jaleswar Sarkar, Bhadrak Sarkar, Cuttack Sarkar, Chicacole (Srikakulam) Sarkar, Kalinga Dandapat and Rajamundry Sarkar or Godavari Province. Odisha's Central, Northern, Western and Southern hilly areas were ruled independently by Hindu kings. The Nizam of Hyderabad occupied the area between Rajahmundry to Srikakulam in 16th century. Medinipur was attached to Bengal province in 18th century. The remaining parts of Coastal Odisha, were subsequently ceded to the Maratha Empire in 1751.
The British occupied the Northern Circars comprising the southern coast of Odisha as a result of the Carnatic Wars in the early 1760s and incorporated them into the Madras Presidency gradually. In 1803, the British under the British East India Company annexed the Maratha province of Odisha after the Second Anglo-Maratha War. The northern and western districts of Odisha were incorporated into Bengal Presidency. Following famine and floods in 1866, large-scale irrigation projects were undertaken in the last half of the 19th century. The coastal section was separated from Bengal and made into Bihar and Orissa Province in 1912, in response to local agitation for a separate state for the Oriya-speaking people. In 1903, the Utkal Sammilani organization was founded with 62 “permanent members” who campaigned for the unification of the state of Odisha. In 1936, Bihar and Odisha were split into separate provinces. Thus after a long period of struggle the Oriya people got re-united after centuries of political separation. On 1 April 1936, the new province of Odisha came into existence on linguistic basis during the British rule in India with Sir John Austin Hubback as the first Governor. A long cherished dream of Oriya people and their leaders like Madhusudan Das, Maharaja Krushna Chandra Gajapati, Pandit Nilakantha Das, Bhubanananda Das and many other came true. The district of Ganjam was transferred from Madras Presidency to the new province of Odisha on 1 April 1936. From that time onwards people of Odisha celebrate the 1 April as Utkal Divas or Odisha Day.
Following Indian independence, the area of Odisha was almost doubled, and the population increased by a third, by the addition of 24 former princely states. In 1950, Odisha became a constituent state in the Union of India.