In its long history spanning more than just the present millennium, the region of modern Orissa was known by different names at different points of time-Kalinga, Utkala, Kongada and Odr-desha.
Ancient Orissa had a number of important ports such as Paloura, Tamralipti and Dharmra along Orissa's 482 km long open coastline. It is little wonder then that a flourishing maritime trade existed between Paloura (now Puri) and the Indonesian islands. As a result, the influence of the Pali language and Buddhism spread, in due course, to Southeast Asia. The old Buddhist connection with these regions is visible in the 'Peace Pagoda' built by the Japanese Buddhists in this century and the Dhavateswar temple on the Dhauli hilltop near Bhubaneswar.
It is noteworthy that the first Aryan immigration from India into Ceylon also took place from the shores of Kalinga. The first known history of the state comes into light with the Ashokan victory over the independent ruler of this place, which led to mass killings and devastation of the region. The extent of violence perpetrated by his men and its effect of the victims led to a change in the heart of Ashoka and he accepted Buddhism as his way of life.
In the first century BC, under King Kharvel, the most famous of Kalinga rulers, Buddhism declined as the major religion and Jainism was restored. The cave inscriptions of Khandgiri and Udayagiri give a lot of information about the rule of King Kharvel and much other information about the society at that point of time.
Later, Jainism gave way to Hinduism in around 7th century AD. This was the time when the ruling dynasties were the Ganga and Kesari, who constructed some of the most magnificent temples in India.
After the decline of these dynasties, the local kingdoms fought hard to keep the Muslims away, but by the end in 16th century, the Mughals defeated them and gained control over this region. After the decline of the Mughals, Orissa was ruled by the Marathas and the British. Orissa became a separate province under the British Government in 1936.