 Following General of the Army Douglas MacArthur 's dismissal as Commander @-@ in @-@ Chief of UN forces in Korea , he was replaced by General Matthew B. Ridgway . Consequently , on 14 April 1951 , General James Van Fleet replaced Ridgway as commander of the US Eighth Army and the United Nations forces in Korea . The Chinese Spring Offensive during April and May 1951 ended in its defeat , while following two months of sporadic operations in mid @-@ June and August , the war entered a new phase , with Van Fleet returning to the offensive . In July the Kansas and Wyoming Lines were strengthened , while a limited offensive in the east @-@ central sector in mid @-@ August seized the high ground around the <unk> and Bloody Ridge during the Battle of Bloody Ridge . In September the offensive in this sector continued , targeting the next hill complex north of Bloody Ridge , known as Heartbreak Ridge . 
