Question: When did the country that manufactures the Koksan gun split from the country the U.S. helped in the Korean War?

full_context: Document 1: Koksan (artillery): The M-1978 Koksan is a 170 mm self-propelled gun of North Korean design and manufacture. Very little information is available due to the secretive nature of the North Korean government. The designations "M-1978" and "Koksan" were given to the type by American military analysts, as they first became aware of it in that year in Koksan, North Korea.
Document 2: History of Korea: After the end of WWII in 1945, the Allies divided the country into a northern area, protected by the Soviets, and a southern area protected primarily by the United States. In 1948, when the powers failed to agree on the formation of a single government, this partition became the modern states of North and South Korea. The peninsula was divided at the 38th Parallel: the ``Republic of Korea ''was created in the south, with the backing of the US and Western Europe, and the`` Democratic People's Republic of Korea'' in the north, with the backing of the Soviets and the communist People's Republic of China. The new premier of North Korea, Kim il - Sung launched the Korean War in 1950 in an attempt to reunify the country under Communist rule. After immense material and human destruction, the conflict ended with a cease - fire in 1953. The two nations officially remain at war because a peace treaty was never signed. Both states were accepted into the United Nations in 1991.
Document 3: Korean War: The Battle of Osan, the first significant American engagement of the Korean War, involved the 540-soldier Task Force Smith, which was a small forward element of the 24th Infantry Division which had been flown in from Japan. On 5 July 1950, Task Force Smith attacked the North Koreans at Osan but without weapons capable of destroying the North Koreans' tanks. They were unsuccessful; the result was 180 dead, wounded, or taken prisoner. The KPA progressed southwards, pushing back the US force at Pyongtaek, Chonan, and Chochiwon, forcing the 24th Division's retreat to Taejeon, which the KPA captured in the Battle of Taejon; the 24th Division suffered 3,602 dead and wounded and 2,962 captured, including the Division's Commander, Major General William F. Dean.
Document 4: Military Demarcation Line: The Military Demarcation Line (MDL), sometimes referred to as the Armistice Line, is the 154 mile - long land border or demarcation line between North Korea and South Korea. On either side of the line is the Korean Demilitarized Zone (DMZ). The MDL and DMZ were established by the Armistice at the end of the Korean War in 1953.
Document 5: Division of Korea: The division of Korea between North and South Korea occurred after World War II, ending the Empire of Japan's 35 - year rule over Korea in 1945. The United States and the Soviet Union each occupied a portion of the peninsula, with the boundary between their zones of control along the 38th parallel.
Document 6: United States in the Korean War: In response to North Korea's invasion into South Korea the United Nations convened to formulate a response. The U.N. demanded North Korea's immediate withdrawal and, when this was not met, United States Army General Douglas MacArthur was appointed supreme commander of U.N. forces. To halt the rapid progress of North Korean forces into the south Task Force Smith was deployed to the Korean front from Japan. Task Force Smith consisted of U.S. Army officers and regiments of the Army's 24th Infantry Division that were stationed in Japan as occupational forces. Unfortunately the 24th were under trained, poorly supplied, and outnumbered. The 24th offered very little resistance against the North Korean advance. American and South Korean troops were pushed south and in late July 1950 Task Force Smith was overrun in the city of Taejon. Troops from the Army's 25th Infantry Division were deployed to Taejon to establish a new line and pullout the decimated 24th I.D. This addition of combat troops did not stop the North Korean advance and both American and South Korean troops were pushed further south.
Document 7: Korean War: By mid-1950, North Korean forces numbered between 150,000 and 200,000 troops, organized into 10 infantry divisions, one tank division, and one air force division, with 210 fighter planes and 280 tanks, who captured scheduled objectives and territory, among them Kaesong, Chuncheon, Uijeongbu, and Ongjin. Their forces included 274 T-34-85 tanks, 200 artillery pieces, 110 attack bombers, some 150 Yak fighter planes, 78 Yak trainers, and 35 reconnaissance aircraft. In addition to the invasion force, the North KPA had 114 fighters, 78 bombers, 105 T-34-85 tanks, and some 30,000 soldiers stationed in reserve in North Korea. Although each navy consisted of only several small warships, the North and South Korean navies fought in the war as sea-borne artillery for their in-country armies.
Document 8: Korean War: The Demilitarized Zone runs northeast of the 38th parallel; to the south, it travels west. The old Korean capital city of Kaesong, site of the armistice negotiations, originally was in pre-war South Korea, but now is part of North Korea. The United Nations Command, supported by the United States, the North Korean People's Army, and the Chinese People's Volunteers, signed the Armistice Agreement on 27 July 1953 to end the fighting. The Armistice also called upon the governments of South Korea, North Korea, China and the United States to participate in continued peace talks. The war is considered to have ended at this point, even though there was no peace treaty. North Korea nevertheless claims that it won the Korean War.
Document 9: KM-SAM: The KM-SAM is the middle-tier of South Korea's three-tier aerial and missile defense system. Though it was developed in Russia by the Almaz Design Bureau with assistance from Samsung Thales, LIG Nex1, and Doosan DST, localization and industrialization were done in South Korea enough to consider it an indigenous system. The Cheongung (Iron Hawk) can intercept targets up to an altitude of at a range of . It is to replace upgraded MIM-23 Hawk batteries in South Korea and be made available for export. Almaz-Antey continued with the program after prototypes were transferred and have created a distinctly Russian version called the Vityaz missile system.
Document 10: Military history of the United States: The war started badly for the US and UN. North Korean forces struck massively in the summer of 1950 and nearly drove the outnumbered US and ROK defenders into the sea. However the United Nations intervened, naming Douglas MacArthur commander of its forces, and UN-US-ROK forces held a perimeter around Pusan, gaining time for reinforcement. MacArthur, in a bold but risky move, ordered an amphibious invasion well behind the front lines at Inchon, cutting off and routing the North Koreans and quickly crossing the 38th Parallel into North Korea. As UN forces continued to advance toward the Yalu River on the border with Communist China, the Chinese crossed the Yalu River in October and launched a series of surprise attacks that sent the UN forces reeling back across the 38th Parallel. Truman originally wanted a Rollback strategy to unify Korea; after the Chinese successes he settled for a Containment policy to split the country. MacArthur argued for rollback but was fired by President Harry Truman after disputes over the conduct of the war. Peace negotiations dragged on for two years until President Dwight D. Eisenhower threatened China with nuclear weapons; an armistice was quickly reached with the two Koreas remaining divided at the 38th parallel. North and South Korea are still today in a state of war, having never signed a peace treaty, and American forces remain stationed in South Korea as part of American foreign policy.
Document 11: AEK-971: The AEK-971 is a Russian (formerly the Soviet Union) selective fire 5.45×39mm assault rifle that was developed at the Kovrov Mechanical Plant (KMZ) by chief designer Sergey Koksharov in the late 1970s and 1980s (currently manufactured by Degtyarev Plant).
Document 12: United States in the Korean War: The first battle the Americans entered in the Korean War was the Battle of Osan, where about four hundred strong landed in Pusan airport on the first of July. The American troops were sent off to Taejon the next morning where Major General John H. Church the head of U.S. field headquarters was confident in the US troop's strengths to push back the North Koreans. On July fifth the troops were finally put to the test when North Korean tanks crept towards Osan. The four hundred infantryman of the U.S. also called Task Force Smith opened fire on the North Koreans at 8: 16 am. Only four of the North Korean tanks were destroyed and twenty - nine kept moving forward breaking the US line. At the end of the battle only two more North Korean Tanks and two regiments of North Korean infantry were destroyed. The US had lost the battle, revealing that the mere sight of US troops would not reverse the military balance in Korea. By early August, the North Korean troops had pushed back the US and South Korean troops all the way to Naktong River, which is located about thirty miles from Pusan. The two weeks of fighting following this resulted in the most casualties of US troops than any other equivalent period of this war. However, during this time the US pushed supplies and personnel to Korea and by the end of July South Koreans and US troops outnumbered the North Koreans, although the North had pushed back the US and South by an amazing amount the North had suffered over fifty thousand casualties. Also because North Koreas supply lines were so lengthy and with the US in control of the water and air replenishing there losses were slow.
Document 13: Korean War: As an initial response, Truman called for a naval blockade of North Korea, and was shocked to learn that such a blockade could be imposed only 'on paper', since the U.S. Navy no longer had the warships with which to carry out his request. In fact, because of the extensive defense cuts and the emphasis placed on building a nuclear bomber force, none of the services were in a position to make a robust response with conventional military strength. General Omar Bradley, Chairman of the Joint Chiefs of Staff, was faced with re-organizing and deploying an American military force that was a shadow of its World War II counterpart. The impact of the Truman administration's defense budget cutbacks were now keenly felt, as American troops fought a series of costly rearguard actions. Lacking sufficient anti-tank weapons, artillery or armor, they were driven back down the Korean peninsula to Pusan. In a postwar analysis of the unpreparedness of U.S. Army forces deployed to Korea during the summer and fall of 1950, Army Major General Floyd L. Parks stated that "Many who never lived to tell the tale had to fight the full range of ground warfare from offensive to delaying action, unit by unit, man by man ... [T]hat we were able to snatch victory from the jaws of defeat ... does not relieve us from the blame of having placed our own flesh and blood in such a predicament."
Document 14: Nuclear weapon design: In 1999, nuclear weapon design was in the news again, for the first time in decades. In January, the U.S. House of Representatives released the Cox Report (Christopher Cox R-CA) which alleged that China had somehow acquired classified information about the U.S. W88 warhead. Nine months later, Wen Ho Lee, a Taiwanese immigrant working at Los Alamos, was publicly accused of spying, arrested, and served nine months in pre-trial detention, before the case against him was dismissed. It is not clear that there was, in fact, any espionage.
Document 15: Division of Korea: The subsequent Korean War, which lasted from 1950 to 1953, ended with a stalemate and has left the two Koreas separated by the Korean Demilitarized Zone (DMZ) up to the present day.
ground_truth: 1953
sub_queries: Koksan >> manufacturer Answer: North Korea
who did the us help in the korean war Answer: South Korea
when did North Korea split from #2 Answer: 1953