 The Karenni States were recognized as tributary to British Burma in 1892, when their rulers agreed to accept a stipend from the British government.In the 1930s, the Mawchi Mine in Bawlake was the most important source of tungsten in the world.The Constitution of the Union of Burma in 1947 proclaimed that the three Karenni States be amalgamated into a single constituent state of the union, called Karenni State.