Sir Alexander Mackenzie (1842–1902) joined the Indian Civil Service in 1862. His career began in Bengal, first as an assistant magistrate and then as a secretary to the local government. His report Memorandum on the North-East Frontier of Bengal (1869) was welcomed as a valuable guide to political relations in the area for government officials. This book, first published in 1884, is the updated and developed version of that report. It was extensively researched by Mackenzie, using government records, and was considered to be authoritative on the political relations between the Government and the hill tribes of Assam, Cachar and Chittagong. Mackenzie dedicates a chapter to each tribe and details their response to British colonisation and any negotiations that took place. Relevant notes and reports by officials who had come into contact with the tribes are also included as appendices. Mackenzie's thorough work remains an authoritative historical source today.