 What became Lawngtlai District was incorporated into the South Lushai Hills and administered by the lieutenant governor of Bengal.In 1898 North and South Lushai Hills were merged into the Lushai Hills District and were administered as part of Assam.In 1919, the Lushai Hills, along with some of the other hill districts, were declared "Backward Tracts" under the Government of India Act, and in 1935 this denomination was changed to "excluded area".