 On the night of June 25 , 1950 , 10 divisions of the North Korean People 's Army launched a full @-@ scale invasion on the nation 's neighbor to the south , the Republic of Korea . Advancing with 89 @,@ 000 men in six columns , the North Koreans caught the South Korean Army by surprise , resulting in a disastrous rout for the South Koreans who were disorganized , ill @-@ equipped , and unprepared for war . Numerically superior , North Korean forces destroyed isolated resistance , pushing steadily down the peninsula against the South Koreans who could muster just 38 @,@ 000 men to the front @-@ line to oppose them . The majority of the South Korean forces retreated in the face of the invasion , and by June 28 the North Koreans had captured the capital Seoul , and forced the government and its shattered forces to withdraw further southwards . 
