The Principality of Ruhuna, also referred to as the Kingdom of Ruhuna, is a region of present-day Southern and Eastern Sri Lanka. It was the center of a flourishing civilization and the cultural and economic centers of ancient Sri Lanka. Magama, Tissamaharama and Mahanagakula (now called as Ambalantota), were established here.
Ruhuna was founded around 200 BC by Prince Mahanaga, brother to Devanampiya Tissa of Anuradhapura, after a personal dispute. This region played a vital role in building the nation as well in the establishment of Buddhist culture.
The area identified with Ruhuna in ancient times is mainly the Southern Province, a large part of the Uva Province and small parts of, Sabaragamuwa & Eastern Provinces.