Question: Who led the force that later pushed deep into Polish territory?

full_context: Document 1: Warsaw: There are also many places commemorating the heroic history of Warsaw. Pawiak, an infamous German Gestapo prison now occupied by a Mausoleum of Memory of Martyrdom and the museum, is only the beginning of a walk in the traces of Heroic City. The Warsaw Citadel, an impressive 19th-century fortification built after the defeat of the November Uprising, was a place of martyr for the Poles. Another important monument, the statue of Little Insurgent located at the ramparts of the Old Town, commemorates the children who served as messengers and frontline troops in the Warsaw Uprising, while the impressive Warsaw Uprising Monument by Wincenty Kućma was erected in memory of the largest insurrection of World War II.
Document 2: Warsaw: Warsaw was occupied by Germany from 4 August 1915 until November 1918. The Allied Armistice terms required in Article 12 that Germany withdraw from areas controlled by Russia in 1914, which included Warsaw. Germany did so, and underground leader Piłsudski returned to Warsaw on 11 November and set up what became the Second Polish Republic, with Warsaw the capital. In the course of the Polish-Bolshevik War of 1920, the huge Battle of Warsaw was fought on the eastern outskirts of the city in which the capital was successfully defended and the Red Army defeated. Poland stopped by itself the full brunt of the Red Army and defeated an idea of the "export of the revolution".
Document 3: The Blitz: British air doctrine, since the time of Chief of the Air Staff Hugh Trenchard in the early 1920s, had stressed offence was the best means of defence. British defensive strategy revolved around offensive action, what became known as the cult of the offensive. To prevent German formations from hitting targets in Britain, RAF's Bomber Command would destroy Luftwaffe aircraft on their own bases, aircraft in their factories and fuel reserves by attacking oil plants. This philosophy was impractical as Bomber Command lacked the technology and equipment and needed several years to develop it. This strategy retarded the development of fighter defences in the 1930s. Dowding agreed air defence would require some offensive action, and fighters could not defend Britain alone. Until September 1940, the RAF lacked specialist night-fighting aircraft and relied on anti-aircraft units which were poorly equipped and lacking in numbers.
Document 4: Anti-aircraft warfare: The most extreme case was the Soviet Union, and this model may still be followed in some countries: it was a separate service, on a par with the navy or ground force. In the Soviet Union this was called Voyska PVO, and had both fighter aircraft and ground-based systems. This was divided into two arms, PVO Strany, the Strategic Air defence Service responsible for Air Defence of the Homeland, created in 1941 and becoming an independent service in 1954, and PVO SV, Air Defence of the Ground Forces. Subsequently these became part of the air force and ground forces respectively
Document 5: Warsaw: In 1939, c. 1,300,000 people lived in Warsaw, but in 1945 – only 420,000. During the first years after the war, the population growth was c. 6%, so shortly the city started to suffer from the lack of flats and of areas for new houses. The first remedial measure was the Warsaw area enlargement (1951) – but the city authorities were still forced to introduce residency registration limitations: only the spouses and children of the permanent residents as well as some persons of public importance (like renowned specialists) were allowed to get the registration, hence halving the population growth in the following years. It also bolstered some kind of conviction among Poles that Varsovians thought of themselves as better only because they lived in the capital. Unfortunately this belief still lives on in Poland (although not as much as it used to be) – even though since 1990 there are no limitations to residency registration anymore.
Document 6: Stanisław Kot: From 1945 to 1947 he cooperated with the Provisional Government on National Unity ("Tymczasowy Rząd Jedności Narodowej"), which attempted to bring together the Polish Government in Exile and Soviet-sponsored Polish communist government. During that time he was the Polish ambassador to Rome. Eventually, Stanisław Kot resigned his post in 1947 and remained in exile, fearing a return to Poland, where he was likely to face charges of treason and possible execution. He remained a supporter of the London-based government in exile, and a leader of the Polish People's Party in exile from 1955, until his death in Middlesex, United Kingdom in 1975.
Document 7: Kliment Voroshilov tank: The Kliment Voroshilov (KV) tanks, a series of Soviet heavy tanks named after the Soviet defence commissar and politician Kliment Voroshilov, operated with the Red Army during World War II. The KV tanks were known for their heavy armour protection during the early stages of the war, especially during the first year of the German invasion of the Soviet Union. In certain situations, even a single KV-1 or KV-2 supported by infantry could halt large German formations. The German Wehrmacht at that time rarely deployed its tanks against KVs, as their own armament was too poor to deal with the ""Russischer Koloss"" – "Russian Colossus".
Document 8: Modern history: The Russian Civil War was a multi-party war that occurred within the former Russian Empire after the Russian provisional government collapsed and the Soviets under the domination of the Bolshevik party assumed power, first in Petrograd (St. Petersburg) and then in other places. In the wake of the October Revolution, the old Russian Imperial Army had been demobilized; the volunteer-based Red Guard was the Bolsheviks' main military force, augmented by an armed military component of the Cheka, the Bolshevik state security apparatus. There was an instituted mandatory conscription of the rural peasantry into the Red Army. Opposition of rural Russians to Red Army conscription units was overcome by taking hostages and shooting them when necessary in order to force compliance. Former Tsarist officers were utilized as "military specialists" (voenspetsy), taking their families hostage in order to ensure loyalty. At the start of the war, three-fourths of the Red Army officer corps was composed of former Tsarist officers. By its end, 83% of all Red Army divisional and corps commanders were ex-Tsarist soldiers.
Document 9: Soviet invasion of Poland: The Soviet invasion of Poland was a Soviet military operation that started without a formal declaration of war on 17 September 1939. On that morning, 16 days after Germany invaded Poland from the west, the Soviet Union invaded Poland from the east. Subsequent military operations lasted for the following 20 days and ended on 6 October 1939 with the two - way division and annexation of the entire territory of the Second Polish Republic by both Germany and the Soviet Union. The joint German - Soviet invasion of Poland was secretly agreed to following the signing of the Molotov - Ribbentrop Pact on 23 August 1939.
Document 10: Ukraine: German armies invaded the Soviet Union on 22 June 1941, initiating nearly four years of total war. The Axis initially advanced against desperate but unsuccessful efforts of the Red Army. In the encirclement battle of Kiev, the city was acclaimed as a "Hero City", because of its fierce resistance. More than 600,000 Soviet soldiers (or one-quarter of the Soviet Western Front) were killed or taken captive there, with many suffering severe mistreatment.Although the majority of Ukrainians fought in or alongside the Red Army and Soviet resistance, in Western Ukraine an independent Ukrainian Insurgent Army movement arose (UPA, 1942). Created as armed forces of the underground (Organization of Ukrainian Nationalists, OUN) which had developed in interwar Poland as a reactionary nationalist organization. During the interwar period, the Polish government's policies towards the Ukrainian minority were initially very accommodating, however by the late 1930s they became increasingly harsh due to civil unrest. Both organizations, OUN and UPA supported the goal of an independent Ukrainian state on the territory with a Ukrainian ethnic majority. Although this brought conflict with Nazi Germany, at times the Melnyk wing of the OUN allied with the Nazi forces. Also, UPA divisions carried out massacres of ethnic Poles, which brought reprisals. After the war, the UPA continued to fight the USSR until the 1950s. At the same time, the Ukrainian Liberation Army, another nationalist movement, fought alongside the Nazis.
Document 11: Battle of Warsaw (1920): The battle of Warsaw was fought from August 12–25, 1920 as Red Army forces commanded by Mikhail Tukhachevsky approached the Polish capital of Warsaw and the nearby Modlin Fortress. On August 16, Polish forces commanded by Józef Piłsudski counterattacked from the south, disrupting the enemy's offensive, forcing the Russian forces into a disorganized withdrawal eastward and behind the Neman River. Estimated Russian losses were 10,000 killed, 500 missing, 30,000 wounded, and 66,000 taken prisoner, compared with Polish losses of some 4,500 killed, 10,000 missing, and 22,000 wounded.
Document 12: The Blitz: In the 1920s and 1930s, air power theorists Giulio Douhet and Billy Mitchell espoused the idea that air forces could win wars by themselves, without a need for land and sea fighting. It was thought there was no defence against air attack, particularly at night. Enemy industry, their seats of government, factories and communications could be destroyed, effectively taking away their means to resist. It was also thought the bombing of residential centres would cause a collapse of civilian will, which might have led to the collapse of production and civil life. Democracies, where the populace was allowed to show overt disapproval of the ruling government, were thought particularly vulnerable. This thinking was prevalent in both the RAF and what was then known as the United States Army Air Corps (USAAC) between the two world wars. RAF Bomber Command's policy in particular would attempt to achieve victory through the destruction of civilian will, communications and industry.
Document 13: Warsaw: By July 1944, the Red Army was deep into Polish territory and pursuing the Germans toward Warsaw. Knowing that Stalin was hostile to the idea of an independent Poland, the Polish government-in-exile in London gave orders to the underground Home Army (AK) to try to seize control of Warsaw from the Germans before the Red Army arrived. Thus, on 1 August 1944, as the Red Army was nearing the city, the Warsaw Uprising began. The armed struggle, planned to last 48 hours, was partially successful, however it went on for 63 days. Eventually the Home Army fighters and civilians assisting them were forced to capitulate. They were transported to PoW camps in Germany, while the entire civilian population was expelled. Polish civilian deaths are estimated at between 150,000 and 200,000.
Document 14: Red Army: In the late 1920s and throughout the 1930s, Soviet military theoreticians led by Marshal Mikhail Tukhachevsky developed the deep operations doctrine, a direct consequence of their Polish - Soviet War and Russian Civil War experiences. To achieve victory, deep operations envisage simultaneous corps - and army - size unit maneuvers of simultaneous parallel attacks throughout the depth of the enemy's ground forces, inducing catastrophic defensive failure. The deep battle doctrine relies upon aviation and armor advances in the hope that maneuver warfare offers quick, efficient, and decisive victory. Marshal Tukhachevsky said that aerial warfare must be ``employed against targets beyond the range of infantry, artillery, and other arms. For maximum tactical effect aircraft should be employed en masse, concentrated in time and space, against targets of the highest tactical importance. ''
Document 15: Korean War: Soviet generals with extensive combat experience from the Second World War were sent to North Korea as the Soviet Advisory Group. These generals completed the plans for the attack by May. The original plans called for a skirmish to be initiated in the Ongjin Peninsula on the west coast of Korea. The North Koreans would then launch a "counterattack" that would capture Seoul and encircle and destroy the South Korean army. The final stage would involve destroying South Korean government remnants, capturing the rest of South Korea, including the ports.
ground_truth: Marshal Mikhail Tukhachevsky
sub_queries: What army was pushing deep into Polish territory to pursue the Germans in 1944? Answer: the Red Army
who led the Red Army and made it an effective fighting force Answer: Marshal Mikhail Tukhachevsky