The Kandyan Convention is a unique document for both national and international community. It was signed on 2nd March, 1815 at the Palace in the city of Kandy. It has been a document prepared for a settlement between British Empire and the Kandyan Kingdom. Sir Robert Brownrigg, the Governor of the British settlements and territories in the Island of Ceylon signed on behalf of the Kandyan Kingdom signed on behalf of the Kandyan Kingdom. It contained 12 clauses by which the King of Britain, His Majesty George III vested with sovere with vested with sovereignty of whole country.This document is significant and unique for the world as it is the one and the only document drafted by the British for the defeated country and gained sovereignty of the whole country. The Convention had been drafted taking into consideration the values of the local people, especially focusing on the prevailed local cast system, customs and religions. Hence, the twelve (12) clauses in the Kandyan Convention reflected political, Economical and social background of Ceylon and the colonies in the Indian Ocean region in general under the British during 1800 s.When the national significances of this document taken into consideration the mosr striking factor is that the cessation of the Sinhalese monarchy with this Convention. It was the first and lasr time that a foreign state to gained sovereignty of the whole Island of Ceylon by a peaceful agreement. With the implementation of Kandyan Convention, the vast changes of political, economic, social and religious have been taken place in local society with the influence of this unique document.