After the First Battle of Naktong Bulge, the US 2nd Infantry Division was moved to defend the Naktong River line. The division, which was untried in combat, was struck with a strong attack by several KPA divisions which crossed the river and struck all along the division's line. The force of the attack split the 2nd Infantry Division in half, and the KPA were able to penetrate to Yongsan, promoting a fight there.
