The Korean war was the war between the two Koreas. The Korean war started when North Korea crossed the 38th parallel and invaded South Korea. South Korea was not at all prepared for war while North Korea was invading with tanks. Immediately South Korea requested back up and the USA came. By the time the US came North Korea had cornered South Korea in the corner which made it much more easy for the US to get resources to South Korea and the US helped South Korea push North Korea back. eventually the US and South Korea regained Seul (South Koreas capital). After a while the US and South Korea started pushing past the 38th parallel and started cornering North Korea. The Us and South Korea almost had victory because they had completely cornered North Korea when China sent in hundred of thousands of troops and they came into North Korea and started pushing the US back because they thought that the US was attacking. The US ordered a full retreat and China pushed the Us all the way back to the 38th parallel. The war went on back and forth for a while but no side really had any major pushes. They both made some minor pushes where they got a little bit past the 38th parallel but it mostly stayed around the 38th parallel and eventually the war started to fizzle out. Still to this day the rivalry between North Korea andSouth Korea is very tight and the war just made that rivalry tighter.