With the Kangwha treaty in 1876 Korea ended its period of isolation and became exposed to foreign pressures. In 1906, after a period of turmoil in Asian international affairs, Korea was declared a Japanese protectorate, and in 1910 it became a colony of that country. Korea remained a Japanese possession until the end of the Pacific War in 1945. This essay is concerned with some of the economic and social changes that took place in Korea under Japanese rule. The first part of the paper discusses the reorganization of the traditional economy by changes in institutional control over it, and the second part describes the growth of the economy during these years.