Question: When did the country that the battle at Riva Ridge took place in surrender to the Allies during WWII?

full_context: Document 1: Armistice of Cassibile: The Armistice of Cassibile was an armistice signed on 3 September 1943 by Walter Bedell Smith and Giuseppe Castellano, and made public on 8 September, between the Kingdom of Italy and the Allies of World War II. It was signed at a conference of generals from both sides in an Allied military camp at Cassibile in Sicily, which had recently been occupied by the Allies. The armistice was approved by both King Victor Emmanuel III and Italian Prime Minister Pietro Badoglio. The armistice stipulated the surrender of Italy to the Allies.
Document 2: Armistice of 22 June 1940: The Armistice of 22 June 1940 was signed at 18: 36 near Compiègne, France, by officials of Nazi Germany and the French Third Republic. It did not come into effect until after midnight on 25 June.
Document 3: Alps: By 1940 the Third Reich had occupied many of the Alpine countries. Austria underwent a political coup that made it part of the Third Reich; France had been invaded and Italy was a fascist regime. Switzerland was the only country to luckily avoid invasion. The Swiss Confederate mobilized its troops—the country follows the doctrine of "armed neutrality" with all males required to have military training—a number that General Eisenhower estimated to be about 850,000. The Swiss commanders wired the infrastructure leading into the country, and threatening to destroy bridges, railway tunnels and passes in the event of a Nazi invasion, and then they retreated to the heart of the mountain peaks where conditions were harsher and a military invasion would involve difficult and protracted battles.
Document 4: Josip Broz Tito: After the Partisans managed to endure and avoid these intense Axis attacks between January and June 1943, and the extent of Chetnik collaboration became evident, Allied leaders switched their support from Draža Mihailović to Tito. King Peter II, American President Franklin Roosevelt and British Prime Minister Winston Churchill joined Soviet Premier Joseph Stalin in officially recognising Tito and the Partisans at the Tehran Conference. This resulted in Allied aid being parachuted behind Axis lines to assist the Partisans. On 17 June 1944 on the Dalmatian island of Vis, the Treaty of Vis (Viški sporazum) was signed in an attempt to merge Tito's government (the AVNOJ) with the government in exile of King Peter II. The Balkan Air Force was formed in June 1944 to control operations that were mainly aimed at aiding his forces.
Document 5: Dwight D. Eisenhower: After the capitulation of Axis forces in North Africa, Eisenhower oversaw the highly successful invasion of Sicily. Once Mussolini, the Italian leader, had fallen in Italy, the Allies switched their attention to the mainland with Operation Avalanche. But while Eisenhower argued with President Roosevelt and British Prime Minister Churchill, who both insisted on unconditional terms of surrender in exchange for helping the Italians, the Germans pursued an aggressive buildup of forces in the country – making the job more difficult, by adding 19 divisions and initially outnumbering the Allied forces 2 to 1; nevertheless, the invasion of Italy was highly successful.
Document 6: Alpine Fortress: The Alpine Fortress () or Alpine Redoubt was the World War II national redoubt planned by Heinrich Himmler in November and December 1943 for Germany's government and armed forces to retreat to an area from "southern Bavaria across western Austria to northern Italy". The plan was never fully endorsed by Hitler and no serious attempt was made to put the plan into operation, although it would serve as an effective tool of propaganda and military deception by the Germans in the final stages of the war.
Document 7: Military history of Italy during World War II: However Italy's conquests were always heavily contested, both by various insurgencies (most prominently the Greek resistance and Yugoslav partisans) and Allied military forces, which waged the Battle of the Mediterranean throughout and beyond Italy's participation. Ultimately the Italian empire collapsed after disastrous defeats in the Eastern European and North African campaigns. In July 1943, following the Allied invasion of Sicily, Benito Mussolini was arrested by order of King Victor Emmanuel III, provoking a civil war. Italy's military outside of the peninsula itself collapsed, its occupied and annexed territories falling under German control. Italy surrendered to the Allies at the end of the Italian Campaign.
Document 8: Alps: Ski troops were trained for the war, and battles were waged in mountainous areas such as the battle at Riva Ridge in Italy, where the American 10th Mountain Division encountered heavy resistance in February 1945. At the end of the war, a substantial amount of Nazi plunder was found stored in Austria, where Hitler had hoped to retreat as the war drew to a close. The salt mines surrounding the Altaussee area, where American troops found 75 kilos of gold coins stored in a single mine, were used to store looted art, jewels, and currency; vast quantities of looted art were found and returned to the owners.
Document 9: Battle of Stalingrad: Bitter fighting raged for every ruin, street, factory, house, basement, and staircase. Even the sewers were the sites of firefights. The Germans called this unseen urban warfare Rattenkrieg ("Rat War"), and bitterly joked about capturing the kitchen but still fighting for the living room and the bedroom. Buildings had to be cleared room by room through the bombed-out debris of residential neighborhoods, office blocks, basements and apartment high-rises. Some of the taller buildings, blasted into roofless shells by earlier German aerial bombardment, saw floor-by-floor, close quarters combat, with the Germans and Soviets on alternate levels, firing at each other through holes in the floors. Fighting on and around Mamayev Kurgan, a prominent hill above the city, was particularly merciless; indeed, the position changed hands many times.
Document 10: Alatsee: Alatsee is a meromictic lake in Ostallgäu, Bavaria, Germany. At an elevation of 868.0 m, its surface area is 12.00 ha. This lake supposedly holds "Hitler's gold". Many divers have died or disappeared mysteriously in this lake due to the toxicity of the organisms living in this lake. These organisms create the "blood cloud " that occurs quite abundantly throughout the year.
Document 11: Alps: Austrian-born Adolf Hitler had a lifelong romantic fascination with the Alps and by the 1930s established a home in the Obersalzberg region outside of Berchtesgaden. His first visit to the area was in 1923 and he maintained a strong tie there until the end of his life. At the end of World War II the US Army occupied Obersalzberg, to prevent Hitler from retreating with the Wehrmacht into the mountains.
Document 12: Military history of Italy during World War II: Some 28 Italian divisions participated in the Balkan invasions. The coast of Yugoslavia was occupied by the Italian Army, while the rest of the country was divided between the Axis forces (a German and Italian puppet State of Croatia was created, under the nominal sovereignty of Prince Aimone, Duke of Aosta, but actually governed by the Croatian fascist Ante Pavelić). The Italians assumed control of most of Greece with their 11th Army, while the Bulgarians occupied the northern provinces and the Germans the strategically most important areas. Italian troops would occupy parts of Greece and Yugoslavia until the Italian armistice with the Allies in September 1943.
Document 13: Alps: A mummified man, determined to be 5,000 years old, was discovered on a glacier at the Austrian–Italian border in 1991. By the 6th century BC, the Celtic La Tène culture was well established. Hannibal famously crossed the Alps with a herd of elephants, and the Romans had settlements in the region. In 1800 Napoleon crossed one of the mountain passes with an army of 40,000. The 18th and 19th centuries saw an influx of naturalists, writers, and artists, in particular the Romantics, followed by the golden age of alpinism as mountaineers began to ascend the peaks. In World War II, Adolf Hitler kept a base of operation in the Bavarian Alps throughout the war.
Document 14: Alps: Celtic tribes settled in Switzerland between 1000 to 1500 BC. The Raetians lived in the eastern regions, while the west was occupied by the Helvetii and the Allobrogi settled in the Rhone valley and in Savoy. Among the many substances Celtic tribes mined was salt in areas such as Salzburg in Austria where evidence of the Hallstatt culture was found by a mine manager in the 19th century. By the 6th century BC the La Tène culture was well established in the region, and became known for high quality decorated weapons and jewelry. The Celts were the most widespread of the mountain tribes—they had warriors that were strong, tall and fair skinned skilled with iron weapons, which gave them an advantage in warfare.
Document 15: Military history of Italy during World War II: The participation of Italy in the Second World War was characterized by a complex framework of ideology, politics, and diplomacy, while its military actions were often heavily influenced by external factors. The imperial ambitions of the Fascist regime, which aspired to restore the Roman Empire in North Africa and the Mediterranean (the Mare Nostrum, or the Italian Empire), were partially met with the annexation of Albania and the Province of Ljubljana, and the occupation of British Somaliland and other territories, but ultimately collapsed after defeats in the East and North African campaigns. In July 1943, following the Allied invasion of Sicily, Benito Mussolini was arrested by order of King Victor Emmanuel III, provoking a civil war. Italy surrendered to the Allies at the end of the Italian Campaign. The northern half of the country was occupied by Germans with the fascists help and made a collaborationist puppet state (with more than 600,000 soldiers), while the south was governed by monarchist and liberal forces, which fought for the Allied cause as the Italian Co-Belligerent Army (at its height numbering more than 50,000 men), helped by circa 350,000 partisans of disparate political ideologies that operated all over Italy.
ground_truth: 3 September 1943
sub_queries: Where was the battle at Riva Ridge? Answer: Italy
when did Italy surrender to the allies in ww2 Answer: 3 September 1943