Question

By July of 1950, North Korean forces had pushed South Korean forces as far south as?

Answer 1

They were pushed back to the Pusan Perimeter- the area around the town and port of Pusan, in the south of the peninsula.

What followed afterwards was the Battle of Pusan Perimeter, won by the United Nations (US, South Vietnam and others), after which the North Korean Army was pushed back to the North.