The first allied troops to arrive in korea were poorly equipped and supplied, and the north koreans drove them back as far as a port city in the southeast corner of korea. seoul pyongyang inchon pusan

This occurred during the "Battle of Pusan Perimeter". The allied troops that were not equipped well with supplies were repeatedly defeated as the North Korean army forced them as far as the Pusan Perimeter. This perimeter served as a defensive line surrounding the area of the southeastern part of the Korean Peninsula including the port of Pusan.