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|World War II|
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Resistance movements during World War II occurred in every occupied country by a variety of means, ranging from non-cooperation, disinformation and propaganda, to hiding crashed pilots and even to outright warfare and the recapturing of towns. In many countries, resistance movements were sometimes also referred to as The Underground.
Among the most notable resistance movements were the Polish Resistance, including the Polish Home Army, Leśni, and the whole Polish Underground State; Yugoslav Partisans, the Soviet partisans,[a] the Italian Resistenza led mainly by the Italian CLN; the French Resistance, the Belgian Resistance, the Norwegian Resistance, the Danish Resistance, the Greek Resistance, the Dutch Resistance and the politically persecuted opposition in Germany itself (there were 16 main resistance groups and at least 27 failed attempts to assassinate Hitler with many more planned): in short, across German-occupied Europe.
Many countries had resistance movements dedicated to fighting the Axis invaders, and Nazi Germany itself also had an anti-Nazi movement. Although Britain was not occupied during the war, the British made complex preparations for a British resistance movement. The main organisation was created by the Secret Intelligence Service (SIS, aka MI6) and is now known as Section VII. In addition there was a short-term secret commando force called the Auxiliary Units. Various organizations were also formed to establish foreign resistance cells or support existing resistance movements, like the British Special Operations Executive and the American Office of Strategic Services (the forerunner of the Central Intelligence Agency).
There were also resistance movements fighting against the Allied invaders. In Italian East Africa, after the Italian forces were defeated during the East African Campaign, some Italians participated in a guerrilla war against the British (1941–1943). The German Nazi resistance movement ("Werwolf") never amounted to much. The "Forest Brothers" of Estonia, Latvia and Lithuania included many fighters who operated against the Soviet occupation of the Baltic States into the 1960s. During or after the war, similar anti-Soviet resistance rose up in places like Romania, Poland, Bulgaria, Ukraine, and Chechnya. While the Japanese were famous for "fighting to the last man", Japanese holdouts tended to be individually motivated and there is little indication that there was any organized Japanese resistance after the war.
After the first shock following the Blitzkrieg, people slowly started to get organized, both locally and on a larger scale, especially when Jews and other groups were starting to be deported and used for the Arbeitseinsatz (forced labor for the Germans). Organization was dangerous, so much resistance was done by individuals. The possibilities depended much on the terrain; where there were large tracts of uninhabited land, especially hills and forests, resistance could more easily get organised undetected. This favoured in particular the Soviet partisans in Eastern Europe. In the much more densely populated Netherlands, the Biesbosch wilderness could be used to go into hiding. In northern Italy, both the Alps and the Apennines offered shelter to partisan brigades, though many groups operated directly inside the major cities.
There were many different types of groups, ranging in activity from humanitarian aid to armed resistance, and sometimes cooperating to a varying degree. Resistance usually arose spontaneously, but was encouraged and helped mainly from London and Moscow.
Various forms of resistance were:
In March 1940, a partisan unit of the first guerilla organization of the Second World War in Europe, led by Major Henryk Dobrzański (Hubal) completely destroyed a battalion of German infantry in a skirmish near the Polish village of Huciska. A few days later in an ambush near the village of Szałasy it inflicted heavy casualties upon another German unit. As time progressed, resistance forces grew in size and number. To counter this threat, the German authorities formed a special 1,000 man-strong anti-partisan unit of combined SS-Wehrmacht forces, including a Panzer group. Although Dobrzański's unit never exceeded 300 men, the Germans fielded at least 8,000 men in the area to secure it.
In 1940, Witold Pilecki, Polish resistance, presented to his superiors a plan to enter Germany's Auschwitz concentration camp, gather intelligence on the camp from the inside, and organize inmate resistance. The Home Army approved this plan, provided him with a false identity card, and on 19 September 1940, he deliberately went out during a street roundup in Warsaw-łapanka, and was caught by the Germans along with other civilians and sent to Auschwitz. In the camp he organized the underground organization Związek Organizacji Wojskowej (ZOW). From October 1940, ZOW sent the first reports about the camp and its genocide to Home Army Headquarters in Warsaw through the resistance network organized in Auschwitz.
On the night of January 21–22, 1940, in the Soviet-occupied Podolian town of Czortków, the Czortków Uprising started. It was the first Polish uprising and the first anti-Soviet uprising of World War II. Anti-Soviet Poles, most of them teenagers from local high schools, stormed the local Red Army barracks and a prison, in order to release Polish soldiers kept there.
1940 was the year of establishing Warsaw Ghetto and infamous death camp Auschwitz-Birkenau by the German Nazis in occupied Poland. Among the many activities of Polish resistance and Polish people one was helping endangered Jews. Polish citizens have the world's highest count of individuals who have been recognized as Righteous Among the Nations by Yad Vashem as non-Jews who risked their lives to save Jews from extermination during the Holocaust.
One of the events that helped the growth of the French Resistance was the targeting of the French Jews, Communists, Gypsies, homosexuals, Catholics, and others, forcing many into hiding. This in turn gave the French Resistance new people to incorporate into their political structures.
The 'Special Operations Executive' SOE was a British World War II organisation. Following Cabinet approval, it was officially formed by Minister of Economic Warfare Hugh Dalton on 22 July 1940, to develop a spirit of resistance in the occupied countries and to prepare a fifth column of resistance fighters to engage in open opposition to the occupiers at such time that the United Kingdom was able to return to the continent. To aid in the transport of agents and the supply of the resistance fighters, a Royal Air Force Special Duty Service was developed. Whereas the SIS was primarily involved in espionage, the SOE and the resistance fighters were geared toward reconnaissance of German defenses and sabotage. In England the SOE was also involved in the formation of the Auxiliary Units, a top secret stay-behind resistance organisation which would have been activated in the event of a German invasion of Britain. The SOE operated in all countries or former countries occupied by or attacked by the Axis forces, except where demarcation lines were agreed with Britain's principal allies (the Soviet Union and the United States).
After the war, the organisation was officially dissolved on 15 January 1946.
In February 1941, the Dutch Communist Party organized a general strike in Amsterdam and surrounding cities, known as the February strike, in protest against anti-Jewish measures by the Nazi occupying force and violence by fascist street fighters against Jews. Several hundreds of thousands of people participated in the strike. The strike was put down by the Nazis and some participants were executed.
In April 1941, the Liberation Front of the Slovene Nation was established in the Province of Ljubljana. Its armed wing were the Slovene Partisans. It represented both the working class and the Slovene ethnicity.
From April 1941, Bureau of Information and Propaganda of the Union for Armed Struggle started in Poland Operation N headed by Tadeusz Żenczykowski. Action was complex of sabotage, subversion and black-propaganda activities carried out by the Polish resistance against Nazi German occupation forces during World War II
Beginning in March 1941, Witold Pilecki's reports were being forwarded via the Polish resistance to the Polish government in exile and through it, to the British government in London and other Allied governments. These reports were the first information about the Holocaust and the principal source of intelligence on Auschwitz for the Western Allies.
In May 1941, the Resistance Team "Elevtheria" (Freedom) was established in Thessaloniki by politicians Paraskevas Barbas, Apostolos Tzanis, Ioannis Passalidis, Simos Kerasidis, Athanasios Fidas, Ioannis Evthimiadis and military officer Dimitrios Psarros. Its armed wing concluded two armed forces; Athanasios Diakos with armed action in Kroussia, with Christodoulos Moschos (captain "Petros") as leader, and Odysseas Androutsos with armed action in Visaltia, with Athanasios Genios (captain "Lassanis") as leader.
Also on June 22, 1941 as a reaction to Nazi invasion of USSR Sisak People's Liberation Partisan Detachment was formed in Croatia, near the town of Sisak. It was first armed Anti-Fascist partisan detachment in Croatia.
Communist-initiated uprising against Axis started in Serbia on July 7, 1941., and six days later in Montenegro. The Republic of Užice (Ужичка република) was a short-lived liberated Yugoslav territory, the first part of occupied Europe to be liberated. Organized as a military mini-state it existed throughout the autumn of 1941 in the western part of Serbia. The Republic was established by the Partisan resistance movement and its administrative center was in the town of Užice. The government was made of "people's councils" (odbors), and the Communists opened schools and published a newspaper, Borba (meaning "Struggle"). They even managed to run a postal system and around 145 km (90 mi) of railway and operated an ammunition factory from the vaults beneath the bank in Užice.
In July 1941 Mieczysław Słowikowski (using the codename "Rygor"—Polish for "Rigor") set up "Agency Africa," one of World War II's most successful intelligence organizations. His Polish allies in these endeavors included Lt. Col. Gwido Langer and Major Maksymilian Ciężki. The information gathered by the Agency was used by the Americans and British in planning the amphibious November 1942 Operation Torch landings in North Africa.
On 13 July 1941, in Italian-occupied Montenegro, Montenegrin separatist Sekula Drljević proclaimed an Independent State of Montenegro under Italian protectorate, upon which a nationwide rebellion escalated raised by Partisans, Yugoslav Royal officers and various other armed personnel. It was the first organized armed uprising in then occupied Europe, and involved 32,000 people. Most of Montenegro was quickly liberated, except major cities where Italian forces were well fortified. On 12 August — after a major Italian offensive involving 5 divisions and 30,000 soldiers — the uprising collapsed as units were disintegrating; poor leadership occurred as well as collaboration. The final toll of July 13 uprising in Montenegro was 735 dead, 1120 wounded and 2070 captured Italians and 72 dead and 53 wounded Montenegrins.
On 11 October 1941, in Bulgarian-occupied Prilep, Macedonians attacked post of the Bulgarian occupation police, which was the start of Macedonian resistance against the fascists who occupied Macedonia: Germans, Italians, Bulgarians and Albanians. The resistance finished successfully in August–November 1944 when independent Macedonian state was formed, and later it was added to the Federation - Federal People's Republic of Yugoslavia (later to be SFRJ).
During the time within which Hitler gave his anti-resistance Nacht und Nebel decree - made on the very day of the Attack on Pearl Harbor in the Pacific - the planning for Britain's Operation Anthropoid was underway, as a resistance move during World War II to assassinate Reinhard Heydrich, the Nazi “Protector of Protectorate of Bohemia and Moravia” and the chief of Nazi's final solution, by the Czech resistance in Prague. Over fifteen thousand Czechs were killed in reprisals, with the most infamous incidents being the complete destruction of the towns of Lidice and Ležáky.
The Luxembourgish general strike of 1942 was a passive resistance movement organised within a short time period to protest against a directive that incorporated the Luxembourg youth into the Wehrmacht. A national general strike, originating mainly in Wiltz, paralysed the country and forced the occupying German authorities to respond violently by sentencing 21 strikers to death.
In September 1942, "The Council to Aid Jews Żegota" was founded by Zofia Kossak-Szczucka and Wanda Krahelska-Filipowicz ("Alinka") and made up of Polish Democrats as well as other Catholic activists. Poland was the only country in occupied Europe where there existed such a dedicated secret organization. Half of the Jews who survived the war (thus over 50,000) were aided in some shape or form by Żegota. The most known activist of Żegota was Irena Sendler head of the children's division who saved 2,500 Jewish children by smuggling them out of the Warsaw Ghetto, providing them false documents, and sheltering them in individual and group children's homes outside the Ghetto.
On the night of 7–8 October 1942, Operation Wieniec started. It targeted rail infrastructure near Warsaw. Similar operations aimed at disrupting German transport and communication in occupied Poland occurred in the coming months and years. It targeted railroads, bridges and supply depots, primarily near transport hubs such as Warsaw and Lublin.
On 25 November, Greek guerrillas with the help of twelve British saboteurs carried out a successful operation which disrupted the German ammunition transportation to the German Africa Corps under Rommel—the destruction of Gorgopotamos bridge (Operation Harling).
On 20 June 1942, the most spectacular escape from Auschwitz concentration camp took place. Four Poles, Eugeniusz Bendera, Kazimierz Piechowski, Stanisław Gustaw Jaster and Józef Lempart made a daring escape. The escapees were dressed as members of the SS-Totenkopfverbände, fully armed and in an SS staff car. They drove out the main gate in a stolen Rudolf Hoss automobile Steyr 220 with a smuggled report from Witold Pilecki about the Holocaust. The Germans never recaptured any of them.
The Zamość Uprising was an armed uprising of Armia Krajowa and Bataliony Chłopskie against the forced expulsion of Poles from the Zamość region (Zamość Lands, Zamojszczyzna) under the Nazi Generalplan Ost. Nazi Germans attempting to remove the local Poles from the Greater Zamosc area (through forced removal, transfer to forced labor camps, or, in rare cases, mass murder) to get it ready for German colonization. It lasted from 1942–1944, and despite heavy casualties suffered by the Underground, the Germans failed.
By the middle of 1943 partisan resistance to the Germans and their allies had grown from the dimensions of a mere nuisance to those of a major factor in the general situation. In many parts of occupied Europe Germany was suffering losses at the hands of partisans that he could ill afford. Nowhere were these losses heavier than in Yugoslavia.
In early January 1943, the 20,000 strong main operational group of the Yugoslav Partisans, stationed in western Bosnia, came under ferocious attack by over 150,000 German and Axis troops, supported by about 200 Luftwaffe aircraft in what became known as the Battle of the Neretva (the German codename was "Fall Weiss" or "Case White"). The Axis rallied eleven divisions, six German, three Italian, and two divisions of the Independent State of Croatia (supported by Ustaše formations) as well as a number of Chetnik brigades. The goal was to destroy the Partisan HQ and main field hospital (all Partisan wounded and prisoners faced certain execution), but this was thwarted by the diversion and retreat across the Neretva river, planned by the Partisan supreme command led by Marshal Josip Broz Tito. The main Partisan force escaped into Serbia.
On 19 April 1943, three members of the Belgian resistance movement were able to stop the Twentieth convoy, which was the 20th prisoner transport in Belgium organised by the Germans during World War II. The exceptional action by members of the Belgian resistance occurred to free Jewish and Romani ("gypsy") civilians who were being transported by train from the Dossin army base located in Mechelen, Belgium to the concentration camp Auschwitz. The 20th train convoy transported 1,631 Jews (men, women and children). Some of the prisoners were able to escape and marked this particular kind of liberation action by the Belgian resistance movement as unique in the European history of the Holocaust.
In October 1943, the rescue of the Danish Jews meant that nearly all of the Danish Jews were saved from KZ camps by the Danish resistance. This action is considered one of the bravest and most significant displays of public defiance against the Nazis. However, the action was largely due to the personal intervention of German diplomat Georg Ferdinand Duckwitz, who both leaked news of the intended round up of the Jews to both the Danish opposition and Jewish groups and negotiated with the Swedes to ensure Danish Jews would be accepted in Sweden.
On 26 March 1943 in Warsaw, Operation Arsenal was conducted by the Szare Szeregi (Gray Ranks) Polish Underground formation and led to the release of arrested troop leader Jan Bytnar "Rudy". In an attack on the prison, Bytnar and 24 other prisoners were set free. The Battle of Sutjeska from 15 May-16 June 1943 was a joint attack of the Axis forces that once again attempted to destroy the main Yugoslav Partisan force, near the Sutjeska river in southeastern Bosnia. The Axis rallied 127,000 troops for the offensive, including German, Italian, NDH, Bulgarian and Cossack units, as well as over 300 airplanes (under German operational command), against 18,000 soldiers of the primary Yugoslav Partisans operational group organised in 16 brigades. Facing almost exclusively German troops in the final encirclement, the Yugoslav Partisans finally succeeded in breaking out across the Sutjeska river through the lines of the German 118th Jäger Division, 104th Jäger Division and 369th (Croatian) Infantry Division in the northwestern direction, towards eastern Bosnia. Three brigades and the central hospital with over 2,000 wounded remained surrounded and, following Hitler's instructions, German commander-in-chief General Alexander Löhr ordered and carried out their annihilation, including the wounded and unarmed medical personnel. In addition, Partisan troops suffered from a severe lack of food and medical supplies, and many were struck down by typhoid. However, the failure of the offensive marked a turning point for Yugoslavia during World War II.
Operation Heads started—an action of serial assassinations of the Nazi personnel sentenced to death by the Special Courts for crimes against Polish citizens in occupied Poland. The Resistance fighters of Polish Home Army's unit Agat kill Franz Bürkl during Operation Bürkl in 1943, and Franz Kutschera during Operation Kutschera in 1944. Both men were high-ranking Nazi German SS and secret police officers responsible for the murder and brutal interrogation of thousands of Polish Jews and Polish resistance fighters and supporters.
The Warsaw Ghetto Uprising lasted from 19 April-16 May, and cost the Nazi forces 17 dead and 93 wounded.
On 30 September the German forces occupying the Italian city of Naples were forced out by the townsfolk and the Italian Resistance before the arrival of the first Allied forces in the city on 1 October. This popular uprising is known as the Four days of Naples.
From November 1943, Operation Most III started. The Armia Krajowa provided the Allies with crucial intelligence on the German V-2 rocket. In effect, some 50 kg (110 lb) of the most important parts of the captured V-2, as well as the final report, analyses, sketches and photos, were transported to Brindisi by a Royal Air Force Douglas Dakota aircraft. In late July 1944, the V-2 parts were delivered to London.
In the spring of 1944, a plan was laid out by the Allies to kidnap General Müller, whose harsh repressive measures had earned him the nickname "the Butcher of Crete". The operation was led by Major Patrick Leigh Fermor, together with Captain W. Stanley Moss, Greek SOE agents and Cretan resistance fighters. However, Müller left the island before the plan could be carried out. Undeterred, Fermor decided to abduct General Heinrich Kreipe instead.
On the night of 26 April, General Kreipe left his headquarters in Archanes and headed without escort to his well-guarded residence, "Villa Ariadni", approximately 50 ft 6 in (15.39 m)25 km outside Heraklion. Major Fermor and Captain Moss, dressed as German military policemen, waited for him 1 km (0.62 mi) before his residence. They asked the driver to stop and asked for their papers. As soon as the car stopped, Fermor quickly opened Kreipe's door, rushed in and threatened him with his gun while Moss took the driver's seat. After driving some distance the British left the car, with suitable decoy material being planted that suggesting an escape off the island had been made by submarine, and with the General began a cross-country march. Hunted by German patrols, the group moved across the mountains to reach the southern side of the island, where a British Motor Launch (ML 842, commanded by Brian Coleman) was to pick them up. Eventually, on 14 May 1944, they were picked up (from Peristeres beach near Rhodakino) and transferred to Egypt.
In April–May 1944, the SS launched the daring airborne Raid on Drvar aimed at capturing Marshal Josip Broz Tito, the commander-in-chief of the Yugoslav Partisans, as well as disrupting their leadership and command structure. The Partisan headquarters were in the hills near Drvar, Bosnia at the time. The representatives of the Allies, Britain's Randolph Churchill and Evelyn Waugh, were also present. Elite German SS parachute commando units fought their way to Tito's cave headquarters and exchanged heavy gunfire resulting in numerous casualties on both sides. Interestingly, Chetniks under Draža Mihailović also flocked to the firefight in their own attempt to capture Tito. By the time German forces had penetrated to the cave, however, Tito had already fled the scene. He had a train waiting for him that took him to the town of Jajce. It would appear that Tito and his staff were well prepared for emergencies. The commandos were only able to retrieve Tito’s marshal's uniform, which was later displayed in Vienna. After fierce fighting in and around the village cemetery, the Germans were able to link up with mountain troops. By that time, Tito, his British guests and Partisan survivors were fêted aboard the Royal Navy destroyer HMS Blackmore and her captain Lt. Carson, RN.
An intricate series of resistance operations were launched in France prior to, and during, Operation Overlord. On June 5, 1944, the BBC broadcast a group of unusual sentences, which the Germans knew were code words—possibly for the invasion of Normandy. The BBC would regularly transmit hundreds of personal messages, of which only a few were really significant. A few days before D-Day, the commanding officers of the Resistance heard the first line of Verlaine's poem, "Chanson d'automne", "Les sanglots longs des violons de l'automne" (Long sobs of autumn violins) which meant that the "day" was imminent. When the second line "Blessent mon cœur d'une langueur monotone" (wound my heart with a monotonous langour) was heard, the Resistance knew that the invasion would take place within the next 48 hours. They then knew it was time to go about their respective pre-assigned missions. All over France resistance groups had been coordinated, and various groups throughout the country increased their sabotage. Communications were cut, trains derailed, roads, water towers and ammunition depots destroyed and German garrisons were attacked. Some relayed info about German defensive positions on the beaches of Normandy to American and British commanders by radio, just prior to 6 June. Victory did not come easily; in June and July, in the Vercors plateau a newly reinforced maquis group fought more than 10,000 German soldiers (no Waffen-SS) under General Karl Pflaum and was defeated, with 840 casualties (639 fighters and 201 civilians). Following the Tulle Murders, Major Otto Diekmann's Waffen-SS company wiped out the village of Oradour-sur-Glane on 10 June. The resistance also assisted the later Allied invasion in the south of France (Operation Dragoon). They started insurrections in cities such as Paris when allied forces came close.
Operation Halyard, which took place between August and December 1944, was an Allied airlift operation behind enemy lines during World War II conducted by Chetniks in occupied Yugoslavia. In July 1944, the Office of Strategic Services (OSS) drew up plans to send a team to Chetniks led by General Draža Mihailović in the German-occupied Territory of the Military Commander in Serbia for the purpose of evacuating Allied airmen shot down over that area. This team, known as the Halyard team, was commanded by Lieutenant George Musulin, along with Master Sergeant Michael Rajacich, and Specialist Arthur Jibilian, the radio operator. The team was detailed to the United States Fifteenth Air Force and designated as the 1st Air Crew Rescue Unit. It was the largest rescue operation of American Airmen in history. According to historian Professor Jozo Tomasevich, a report submitted to the OSS showed that 417 Allied airmen who had been downed over occupied Yugoslavia were rescued by Mihailović's Chetniks, and airlifted out by the Fifteenth Air Force. According to Lt. Cmdr. Richard M. Kelly (OSS) grand total of 432 U.S. and 80 Allied personnel were airlifted during the Halyard Mission.
Operation Tempest launched in Poland in 1944 would lead to several major actions by Armia Krajowa, most notable of them being the Warsaw Uprising that took place in between August 1 and October 2, and failed due to the Soviet refusal, due to differences in ideology, to help; another one was Operation Ostra Brama: the Armia Krajowa or Home Army turned the weapons given to them by the Nazi Germans (in hope that they would fight the incoming Soviets) against the nazi Germans—in the end the Home Army together with the Soviet troops took over the Greater Vilnius area to the dismay of the Lithuanians.
On 25 June 1944, the Battle of Osuchy started—one of the largest battles between the Polish resistance and Nazi Germany in occupied Poland during World War II, essentially a continuation of the Zamosc Uprising. During Operation Most III, in 1944, the Polish Home Army or Armia Krajowa provided the British with the parts of the V-2 rocket.
Norwegian sabotages of the German nuclear program drew to a close after three years on 20 February 1944, with the saboteur bombing of the ferry SF Hydro. The ferry was to carry railway cars with heavy water drums from the Vemork hydroelectric plant, where they were produced, across Lake Tinn so they could be shipped to Germany. Its sinking effectively ended Nazi nuclear ambitions. The series of raids on the plant was later dubbed by the British SOE as the most successful act of sabotage in all of World War II, and was used as a basis for the US war movie The Heroes of Telemark.
As an initiation of their uprising, Slovakian rebels entered Banská Bystrica on the morning of 30 August 1944, the second day of the rebellion, and made it their headquarters. By 10 September, the insurgents gained control of large areas of central and eastern Slovakia. That included two captured airfields, and as a result of the two-week-old insurgency, the Soviet Air Force were able to begin flying in equipment to Slovakian and Soviet partisans.
a ^ Sources vary with regard to what was the largest resistance movement during World War II. The confusion often stems from the fact that as war progressed, some resistance movements grew larger - and other diminished. In particular, Polish and Soviet territories were mostly freed from Nazi German control in the years 1944-1945, eliminating the need for their respective (anti-Nazi) partisan forces (in Poland, cursed soldiers continued to fight against the Soviets). Fighting in Yugoslavia, however, with Yugoslavian partisans fighting German units, continued till the end of the war. The numbers for each of those three movements can be roughly estimated as approaching 100,000 in 1941, and 200,000 in 1942, with Polish and Soviet partisan numbers peaking around 1944 at 350,000-400,000, and Yugoslavian, growing till the very end till they reached the 800,000.
Several sources note that Polish Armia Krajowa was the largest resistance movement in Nazi-occupied Europe. For example, Norman Davies wrote "Armia Krajowa (Home Army), the AK, which could fairly claim to be the largest of European resistance"; Gregor Dallas wrote "Home Army (Armia Krajowa or AK) in late 1943 numbered around 400,000, making it the largest resistance organization in Europe"; Mark Wyman wrote "Armia Krajowa was considered the largest underground resistance unit in wartime Europe". Certainly, Polish resistance was the largest resistance till German invasion of Yugoslavia and invasion of the Soviet Union in 1941.
After that point, the numbers of Soviet partisans and Yugoslav partisans begun growing rapidly. The numbers of Soviet partisans quickly caught up and were very similar to that of the Polish resistance (a graph is also available here).
The numbers of Tito's Yugoslav partisans were roughly similar to those of the Polish and Soviet partisans in the first years of the war (1941–1942), but grew rapidly in the latter years, outnumbering the Polish and Soviet partisans by 2:1 or more (estimates give Yugoslavian forces about 800,000 in 1945, to Polish and Soviet forces of 400,000 in 1944). Some authors also call it the largest resistance movement in Nazi-occupied Europe, for example, Kathleen Malley-Morrison wrote: "The Yugoslav partisan guerrilla campaign, which developed into the largest resistance army in occupied Western and Central Europe...".
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