During the era of Chandragupta and Vindusara, Kalinga enjoyed its freedom as a separate and independent state, although it is not sure whether it was ruled by one king or as a group of kingdoms or any democratic form of government.
Ashoka and Kalinga Ashok (son of Vindusara) wanted to annex Kalinga with Magadha for commercial reasons, although some folktales indicates that he invaded for personal reason, but primarily commercial reason is most prominent.