Editing Axis powers (section)

==Other Tripartite Pact signatories==
{{see also|Croatian–Romanian–Slovak friendship proclamation}}

In addition to the three major Axis powers, six other countries signed the [[Tripartite Pact]] as its member states. Of the additional countries, Hungary, Slovakia, Bulgaria, the Independent State of Croatia, and Romania participated in various Axis military operations with their national armed forces, while the sixth, Yugoslavia, saw its Tripartite signatory government overthrown earlier in a coup merely days after it signed the Pact, and the membership was reversed.

===Hungary===
{{Main|Hungary in World War II|Government of National Unity (Hungary)}}
[[File:Toldi.jpg|thumb|Hungarian [[Toldi (tank)|Toldi I]] tank as used during the 1941 Axis invasion of the Soviet Union]]The [[Kingdom of Hungary (1920–1946)|Kingdom of Hungary]], ruled by [[Regent]] Admiral [[Miklós Horthy]], was the first country apart from Germany, Italy, and Japan to adhere to the Tripartite Pact, signing the agreement on 20 November 1940.<ref>Seamus Dunn, T.G. Fraser. Europe and Ethnicity: The First World War and Contemporary Ethnic Conflict. Routledge, 1996. p. 97.</ref>

Political instability plagued the country until Miklós Horthy, a Hungarian nobleman and [[Austro-Hungarian Navy|Austro-Hungarian naval]] officer, became regent in 1920. The vast majority of the Hungarians desired to recover former territories of the [[Lands of the Crown of Saint Stephen]] lost through the [[Treaty of Trianon]]. During the government of [[Gyula Gömbös]], Hungary drew closer to Germany and Italy largely because of a shared desire to revise the peace settlements made after World War I.{{sfn|Montgomery|2002|p={{page needed|date=March 2012}}}} Many people sympathized with the [[anti-Semitism|anti-Semitic]] policy of the Nazi regime. Hungary refused to participate in Nazi Germany's planned invasion of Czechoslovakia during the Sudenten Crisis, but after the Munich Agreement carried out a diplomatic rapprochement in order to avoid Germany developing too close of an alliance with Hungary's rival Romania.<ref name=":1" /> Due to its supportive stance towards Germany and the new efforts in the international policy, Hungary gained favourable territorial settlements by the [[First Vienna Award]], after the breakup of [[Czechoslovakia]] occupied and annexed the remainder of [[Carpathian Ruthenia]] and in 1940 received [[Northern Transylvania]] from Romania via the [[Second Vienna Award]]. Hungarians permitted German troops to transit through their territory during the [[invasion of Yugoslavia]], and Hungarian forces joined the military operations after the proclamation of the Independent State of Croatia. Parts of the former Yugoslavia were annexed to Hungary; the United Kingdom immediately broke off diplomatic relations in response.

[[File:Hungarian soldiers in the Carpathians.jpg|thumb|left|Hungarian soldiers in the [[Carpathian mountains]] in 1944]]
Although Hungary did not initially participate in the [[Operation Barbarossa|German invasion of the Soviet Union]], Hungary and the [[Soviet Union]] became belligerents on 27 June 1941. Over 500,000 soldiers served on the [[Eastern Front (World War II)|Eastern Front]]. All five of Hungary's field armies ultimately participated in the war against the Soviet Union; a significant contribution was made by the [[Hungarian Second Army]].

On 25 November 1941, Hungary was one of thirteen signatories to the renewed Anti-Comintern Pact. Hungarian troops, like their Axis counterparts, were involved in numerous actions against the Soviets. By the end of 1943, the Soviets had gained the upper hand and the Germans were retreating. The Hungarian Second Army was destroyed in fighting on the [[Voronezh Front]], on the banks of the [[Don River (Russia)|Don River]].

Prior to the [[Operation Margarethe|German occupation]] within the area of Hungary around 63,000 Jews perished. Afterwards, in late 1944, 437,000 Jews were deported to Auschwitz-Birkenau, most of them to their deaths.<ref>''Hungary and the Holocaust Confrontation with the Past'' (2001) (Center for Advanced Holocaust Studies United States Holocaust Memorial Museum); Tim Cole;  ''Hungary, the Holocaust, and Hungarians: Remembering Whose History?''  pp. 3–5; [https://www.ushmm.org/m/pdfs/Publication_OP_2001-01.pdf]</ref> Overall, Hungarian Jews suffered close to 560,000 casualties.<ref>Randolph L. Braham; (2010) ''Hungarian, German, and Jewish calculations and miscalculations in the last chapter of the Holocaust'' pp. 9–10; Washington, D.C. : Center for Advanced Holocaust Studies, United States Holocaust Memorial Museum, [https://www.ushmm.org/m/pdfs/Publication_OP_2010-01.pdf]</ref>

[[File:Repülőtér, 1944. április 13. Kass Ferenc őrmester légiharcban megsérült MÁVAG Héja II. vadászrepülőgépe. Fortepan 9233.jpg|thumb|[[MÁVAG Héja]] fighter aircraft, derived from the [[Reggiane Re.2000]], an Italian fighter design]]

Relations between Germany and the regency of [[Miklós Horthy]] collapsed in 1944 when Horthy attempted to negotiate a peace agreement with the Soviets and jump out of the war without German approval. Horthy was forced to abdicate after German commandos, led by Colonel [[Otto Skorzeny]], held his son hostage as part of [[Operation Panzerfaust]]. Hungary was reorganized following Horthy's abdication in December 1944 into a totalitarian regime called the [[Government of National Unity (Hungary)|Government of National Unity]], led by [[Ferenc Szálasi]]. He had been [[Prime Minister of Hungary]] since October 1944 and was leader of the [[Hungarism|Hungarist]] [[Arrow Cross Party]]. Its jurisdiction was effectively limited to an ever-narrowing band of territory in [[central Hungary]], around [[Budapest]] since by the time they took power the [[Red Army]] was already far inside the country. Nonetheless, the Arrow Cross rule, short-lived as it was, was brutal. In fewer than three months, Arrow Cross death squads killed as many as 38,000 [[History of the Jews in Hungary|Hungarian Jews]]. Arrow Cross officers helped [[Adolf Eichmann]] re-activate the deportation proceedings from which the Jews of Budapest had thus far been spared, sending some 80,000 Jews out of the city on slave labour details and many more straight to death camps. Most of them died, including many who were murdered outright after the end of the fighting as they were returning home.<ref name="remeny.org">{{cite web|url=http://www.remeny.org/node/36 |title=Szita Szabolcs: A budapesti csillagos házak (1944–45) &#124; Remény |website=Remeny.org |date=15 February 2006 |access-date=2017-06-17}}</ref><ref>{{cite web|url=http://www.osa.ceu.hu/galeria/sites/siege/section2.html |title=Section2 |access-date=2013-05-18 |url-status = dead|archive-url=https://web.archive.org/web/20090202124928/http://www.osa.ceu.hu/galeria/sites/siege/section2.html |archive-date=2009-02-02 }}</ref> Days after the Szálasi government took power, the capital of [[Budapest]] was surrounded by the Soviet [[Red Army]]. German and Hungarian forces tried to hold off the Soviet advance but failed. After fierce fighting, Budapest was taken by the Soviets. A number of pro-German Hungarians retreated to Italy and Germany, where they fought until the end of the war.

In March 1945, Szálasi fled to Germany as the leader of a government in exile, until the surrender of Germany in May 1945.

===Romania===
{{Main|Romania in World War II|Romanian armored fighting vehicle production during World War II|Romanian Navy during World War II|Kingdom of Romania under Fascism|National Legionary State}}

[[File:IAR80.jpg|thumb|upright|left|A formation of Romanian [[IAR 80]] fighter aircraft]]

With the exception of Germany and Italy, Romania was the only country where a Fascist movement came to power without foreign assistance.<ref>{{Cite book|url=https://books.google.com/books?id=Q1zoXqTR_dAC&pg=PA35|title=Theft of a Nation: Romania Since Communism|first=Tom|last=Gallagher|date=July 30, 2005|publisher=Hurst|isbn=9781850657163 |via=Google Books}}</ref> When war erupted in Europe, the economy of the [[Kingdom of Romania]] was already subordinated to the interests of Nazi Germany through a [[German–Romanian Treaty for the Development of Economic Relations between the Two Countries (1939)|treaty signed in the spring of 1939]]. Nevertheless, the country had not totally abandoned pro-British sympathies. Romania had also been allied to the [[Polish–Romanian alliance|Poles]] for most of the interwar era. Following the [[invasion of Poland]] by Germany and the Soviet Union, and the German conquest of France and the [[Low Countries]], Romania found itself increasingly isolated; meanwhile, pro-German and pro-Fascist elements began to grow.

The August 1939 [[Molotov–Ribbentrop Pact]] between Germany and the Soviet Union contained a secret protocol ceding [[Bessarabia]], and [[Northern Bukovina]] to the Soviet Union.{{sfn|Molotov–Ribbentrop Pact|1939}} On June 28, 1940, the Soviet Union [[Soviet occupation of Bessarabia and northern Bukovina|occupied and annexed Bessarabia, as well as part of northern Romania]] and the [[Hertsa region]].{{sfn|Senn|2007|p={{page needed|date=March 2012}}}} On 30 August 1940, as a result of the [[Nazi Germany|German]]–[[Kingdom of Italy|Italian]] arbitrated [[Second Vienna Award]] Romania had to cede [[Northern Transylvania]] to Hungary. [[Southern Dobruja]] was ceded to [[Bulgaria]] in September 1940. In an effort to appease the Fascist elements within the country and obtain German protection, [[Carol II of Romania|King Carol II]] appointed the General [[Ion Antonescu]] as Prime Minister on September 6, 1940.

[[File:Bundesarchiv Bild 183-B03212, München, Staatsbesuch Jon Antonescu bei Hitler.jpg|thumb|upright|Ion Antonescu and [[Adolf Hitler]] at the ''[[Hochschule für Musik und Theater München|Führerbau]]'' in [[Munich]] (June 1941)]]
Two days later, Antonescu forced the king to abdicate and installed the king's young son [[Michael of Romania|Michael]] (Mihai) on the throne, then declared himself ''[[Conducător]]'' ("Leader") with dictatorial powers. The [[National Legionary State]] was proclaimed on 14 September, with the [[Iron Guard]] ruling together with Antonescu as the sole legal political movement in Romania. Under King Michael I and the military government of Antonescu, Romania signed the [[Tripartite Pact]] on November 23, 1940. German troops entered the country on 10 October 1941, officially to train the [[Romanian Armed Forces|Romanian Army]]. Hitler's directive to the troops on 10 October had stated that "it is necessary to avoid even the slightest semblance of military occupation of Romania".<ref>Dinu C. Giurescu, ''Romania in the Second World War (1939–1945)''</ref> The entrance of German troops in Romania determined Italian dictator [[Benito Mussolini]] to launch an invasion of Greece, starting the [[Greco-Italian War]].<ref>[[Craig Stockings]], Eleanor Hancock, ''Swastika over the Acropolis: Re-interpreting the Nazi Invasion of Greece in World War II'', p. 37</ref> Having secured Hitler's approval in January 1941, Antonescu [[Legionnaires' rebellion and Bucharest pogrom|ousted the Iron Guard]] from power.

Romania was subsequently used as a platform for invasions of Yugoslavia and the Soviet Union. Despite not being involved militarily in the [[Invasion of Yugoslavia]], Romania requested that Hungarian troops not operate in the [[Banat (1941-1944)|Banat]]. Paulus thus modified the Hungarian plan and kept their troops west of the [[Tisza]].<ref>Carlile Aylmer Macartney, ''October Fifteenth: A History of Modern Hungary, 1929–1945, Vol. 1'', p. 481</ref>

Romania joined the German-led invasion of the Soviet Union on June 22, 1941. Antonescu was the only foreign leader Hitler consulted on military matters<ref>Dennis Deletant, ''Final report'', p. 498</ref> and the two would meet no less than ten times throughout the war.<ref>Robert D. Kaplan, ''In Europe's Shadow: Two Cold Wars and a Thirty-Year Journey Through Romania and Beyond'', p. 134</ref> Romania re-captured Bessarabia and Northern Bukovina during [[Operation Munchen]] before conquering further Soviet territory and establishing the [[Transnistria Governorate]]. After the [[Siege of Odessa]], the city became the capital of the Governorate. Romanian troops [[Crimean Campaign|fought their way into the Crimea]] alongside German troops and contributed significantly to the [[Siege of Sevastopol (1941–42)|Siege of Sevastopol]]. Later, Romanian mountain troops joined the German campaign in the Caucasus, reaching as far as [[Nalchik]].<ref>[[David T. Zabecki]], ''World War II in Europe: An Encyclopedia'', p. 1421</ref> After suffering devastating losses [[Romanian armies in the battle of Stalingrad|at Stalingrad]], Romanian officials began secretly negotiating peace conditions with the Allies.

[[File:Mareșal tank destroyer M-05 prototype.jpg|thumb|left|The Romanian [[Mareșal tank destroyer]]'s design was likely used by the Germans to develop the [[Hetzer]].]] 
[[Arms industry in Romania#Weapons produced during World War II and the Interwar period|Romania's military industry]] was small but versatile, able to copy and produce thousands of French, Soviet, German, British, and Czechoslovak weapons systems, as well as producing capable original products.{{sfn|Zaloga|2013|p=31}} The [[Romanian Naval Forces|Romanian Navy]] also built sizable warships, such as the minelayer {{NMS|Amiral Murgescu}} and the submarines {{NMS|Rechinul}} and {{NMS|Marsuinul}}.{{sfn|Axworthy|1995|pp=350–351}} Hundreds of originally-designed [[Romanian Air Force]] aircraft were also produced, such as the fighter [[IAR-80]] and the light bomber [[IAR-37]].{{sfn|Axworthy|1995|pp=239, 243}} The country had [[Romanian armored fighting vehicle production during World War II|built armored fighting vehicles]] as well, most notably the [[Mareșal tank destroyer]], that likely influenced the design of the German [[Hetzer]].{{sfn|Axworthy|1995|p=229}} Romania had also been a major power in the oil industry since the 1800s. It was one of the largest producers in Europe and the [[Ploiești]] oil refineries provided about 30% of all Axis oil production.<ref>{{cite book|last1=Atkinson|first1=Rick|title=The Guns at Last Light|year=2013|publisher=Henry Holt|location=New York|isbn=978-0-8050-6290-8|page=354|edition=1st}}</ref> British historian [[Dennis Deletant]] has asserted that Romania's crucial contributions to the Axis war effort, including having the third largest Axis army in Europe and sustaining the German war effort through oil and other materiel, meant that it was "on a par with Italy as a principal ally of Germany and not in the category of a minor Axis satellite".<ref>Dennis Deletant, "Romania", in [https://books.google.com/books?id=VMk-DwAAQBAJ&dq=romania+minor+Axis+satellite&pg=PA78 David Stahel, ''Joining Hitler's Crusade'' (Cambridge University Press, 2017), p. 78]</ref> Another British historian, Mark Axworthy, believes that Romania could even be considered to have had the second most important Axis army of Europe, even more so than that of Italy.{{sfn|Axworthy|1995|p=9}}

Under Antonescu Romania was a fascist dictatorship and a totalitarian state. Between 45,000 and 60,000 Jews were killed in [[Bukovina]] and [[Bessarabia]] by Romanian and German troops in 1941. According to Wilhelm Filderman at least 150,000 Jews of Bessarabia and Bukovina, died under the Antonescu regime (both those deported and those who remained). Overall, approximately 250,000 Jews under Romanian jurisdiction died.<ref>Radu Ioanid; (2008) ''The Holocaust in Romania: The Destruction of Jews and Gypsies Under the Antonescu Regime 1940–1944'' pp. 289–297; Ivan R. Dee, {{ISBN|1461694906}}</ref>

[[File:Bundesarchiv Bild 101I-218-0501-27, Russland-Süd, rumänische Soldaten.jpg|thumb|right|Romanian soldiers on the outskirts of Stalingrad during the Battle of Stalingrad in 1942]]
By 1943, the tide began to turn. The Soviets pushed further west, retaking Ukraine and eventually launching an [[First Jassy–Kishinev Offensive|unsuccessful invasion]] of eastern Romania in the spring of 1944. Romanian troops in the Crimea [[Kerch-Eltigen Operation|helped repulse initial Soviet landings]], but eventually all of the peninsula was re-conquered by Soviet forces and the [[Romanian Navy]] evacuated over 100,000 German and Romanian troops, an achievement which earned Romanian Admiral [[Horia Macellariu]] the [[Knight's Cross of the Iron Cross]].<ref>Spencer C. Tucker, ''World War II at Sea: An Encyclopedia'', p. 633</ref> During the [[Second Jassy–Kishinev Offensive|Jassy-Kishinev Offensive]] of August 1944, Romania [[King Michael's Coup|switched sides]] on August 23, 1944. Romanian troops then fought alongside the Soviet Army until the end of the war, reaching as far as Czechoslovakia and Austria.

====Germany's main European ally (September 1943 – August 1944)====
After the September 1943 [[Armistice of Cassibile]] with Italy, Romania became the second Axis Power in Europe.<ref name="auto">{{Cite book|url=https://books.google.com/books?id=VMk-DwAAQBAJ&pg=PA78|title=Joining Hitler's Crusade|first=David|last=Stahel|year=2018|publisher=Cambridge University Press|isbn=9781316510346 |via=Google Books}}</ref> The Romanians shared in the spoils of [[Operation Achse]], {{Lang|it|[[Regia Marina]]'s}} 5 [[CB-class midget submarine]]s in the Black Sea being transferred to the Romanian Navy.<ref>{{Cite book|url=https://books.google.com/books?id=8h7OAwAAQBAJ&pg=PA174|title=Mussolini's Navy: A Reference Guide to the Regia Marina 1930–1945|first=Maurizio|last=Brescia|year=2012|publisher=Seaforth Publishing|isbn=9781848321151 |via=Google Books}}</ref> Romania also captured 496 Italians, mostly naval personnel (2 of them later died). Before the month was out, Germany had agreed to systematically supply the Romanian Army with German military vehicles, via the Olivenbaum I-III and Quittenbaum I programs. Deliveries started in November 1943, and by August 1944, Germany had supplied Romania with 10 times more armored vehicles ([[Panzer III]], [[Panzer IV]] and [[Sturmgeschütz III]]) than during the entire pre-Cassibile period. Having acquired the license to produce the [[Messerschmitt Bf 109]], Romania planned to assemble 75 from German parts. Deliveries began in May 1944, but only 6 were completed before Romania left the Axis in August 1944. Eleven more were completed by the end of the war with the remaining 58 completed after the war. In 1944, Romania had also gained access to certain ''[[Wunderwaffe]]n'', such as the [[Werfer-Granate 21]]. The first Romanian-made [[Fiesler Storch]] was completed in October 1943, followed by 9 more by May 1944. From March 1944, Germany also contributed to the design and construction of the M-05 and M-06 prototypes of the Mareșal tank destroyer: [[Alkett]] contributed to the Romanian design team and [[Telefunken]] radios along with [[Böhler]] armor were provided. The [[75 mm Reșița Model 1943|75 mm Reșița gun]] (production started at the end of 1943) used the projectile chamber of the German [[Pak 40]]. Technology transfers between the two countries were not necessarily one-way, however. On 6 January 1944, Antonescu showed Hitler the plans of the M-04 prototype of the [[Mareșal tank destroyer]]. In May 1944, Lieutenant-Colonel Ventz from the ''[[Waffenamt]]'' acknowledged that the ''Hetzer'' had followed the Romanian design. German-led [[Army Group South Ukraine]] could not take major operational decisions without securing [[Ion Antonescu]]'s approval, even as late as 22 August 1944 (the day before [[King Michael's Coup|he was dismissed]]).{{sfn|Axworthy|1995|pp=152–153, 158, 174, 217, 219, 229–232, 236, 249 and 265–266}} An entire German army ([[6th Army (Wehrmacht)|the 6th]]) came under Romanian command in May 1944, when it became part of Romanian general [[Petre Dumitrescu]]'s ''Armeegruppe''. For the first time in the war, German commanders came under the actual (rather than nominal) command of their foreign allies. This Romanian-led army group had 24 divisions of which 17 were German.<ref>{{Cite book|url=https://books.google.com/books?id=e__d6mE5ocsC&pg=PA163|title=The German Defeat in the East 1944–45|first=Samuel W.|last=Mitcham|year=2007|publisher=Stackpole Books|isbn=9780811733717 |via=Google Books}}</ref><ref>{{Cite web|url=https://books.google.com/books?id=rAKmUiGeTyoC&pg=PA57|title=Professional Journal of the United States Army|date=July 30, 1985|publisher=Command and General Staff School|via=Google Books}}</ref>

===Slovakia===
{{Main|Slovak Republic (1939–1945)|Slovakia during World War II|Slovak invasion of Poland}}
[[File:Jozef Tiso (Berlin).jpg|thumb|[[Adolf Hitler]] greeting [[Jozef Tiso]], president of the [[Slovak Republic (1939–1945)|Slovak Republic]], 1941]]

The [[Slovak Republic (1939-1945)|Slovak Republic]] under President [[Josef Tiso]] signed the Tripartite Pact on 24 November 1940.

Slovakia had been closely aligned with Germany almost immediately from its declaration of independence from Czechoslovakia on 14 March 1939. Slovakia entered into a treaty of protection with Germany on 23 March 1939.

[[Slovak invasion of Poland|Slovak troops joined the German invasion of Poland]], having interest in [[Spiš]] and [[Orava (region)|Orava]]. Those two regions, along with [[Cieszyn Silesia]], had been [[Polish-Czechoslovak border conflicts|disputed]] between Poland and Czechoslovakia since 1918. The Poles fully annexed them following the [[Munich Agreement]]. After the invasion of Poland, Slovakia reclaimed control of those territories.
Slovakia invaded Poland alongside German forces, contributing 50,000 men at this stage of the war.

[[File:Japanese envoy Oshima in Bratislava.png|thumb|left|[[Hiroshi Ōshima]], Japanese envoy to Slovak Republic and Ambassador to Germany with Slovak president [[Jozef Tiso]] and Slovak prime minister [[Vojtech Tuka]], 1941]]

Slovakia declared war on the Soviet Union in 1941 and signed the revived Anti-Comintern Pact in 1941. Slovak troops fought on Germany's Eastern Front, furnishing Germany with two divisions totaling 80,000 men. Slovakia declared war on the United Kingdom and the United States in 1942.

Slovakia was spared German military occupation until the [[Slovak National Uprising]], which began on 29 August 1944, and was almost immediately crushed by the Waffen SS and Slovak troops loyal to Josef Tiso.

After the war, Tiso was executed and Slovakia once again became part of Czechoslovakia. The border with Poland was shifted back to the pre-war state.

===Bulgaria===
{{Main|Bulgaria during World War II}}
[[File:Bulgarian army 1941.jpg|thumb|Bulgarian soldiers in [[Vardar Macedonia]] during the Balkans campaign]]

The [[Tsardom of Bulgaria (1908–1946)|Tsardom of Bulgaria]] was ruled by [[Boris III of Bulgaria|Тsar Boris III]] when it signed the Tripartite Pact on 1 March 1941. Bulgaria had been on the losing side in the First World War and sought a return of what the Bulgarian leadership saw as lost ethnically and historically Bulgarian territories, specifically in [[Macedonia (region)|Macedonia]] and [[Thrace]] (divided between the [[Kingdom of Yugoslavia]], the [[Kingdom of Greece]], and Turkey). During the 1930s, because of traditional right-wing elements, Bulgaria drew closer to Nazi Germany. In 1940 Germany pressured Romania to sign the [[Treaty of Craiova]], returning to Bulgaria the region of [[Southern Dobrudja]], which it had lost in 1913. The Germans also promised Bulgaria – if it joined the Axis – an enlargement of its territory to the borders specified in the [[Treaty of San Stefano]].

Bulgaria participated in the [[Axis invasion of Yugoslavia]] and Greece by letting German troops attack from its territory and sent troops to Greece on April 20. As a reward, the Axis powers allowed Bulgaria to occupy parts of both countries{{snd}}southern and south-eastern Yugoslavia ([[Vardar Banovina]]) and north-eastern Greece (parts of [[Greek Macedonia]] and [[Greek Thrace]]). The Bulgarian forces in these areas spent the following years fighting various nationalist groups and [[resistance movement]]s. Despite German pressure, Bulgaria did not take part in the [[Operation Barbarossa|Axis invasion of the Soviet Union]] and actually never declared war on the Soviet Union. The [[Bulgarian Navy]] was nonetheless involved in a number of skirmishes with the Soviet [[Black Sea Fleet]], which attacked Bulgarian shipping.

Following the Japanese attack on Pearl Harbor in December 1941, the Bulgarian government declared war on the [[Allies of World War II|Western Allies]]. This action remained largely symbolic (at least from the Bulgarian perspective), until August 1943, when Bulgarian air defense and air force attacked Allied bombers, returning (heavily damaged) from a mission over the Romanian oil refineries. This turned into a disaster for the citizens of [[Sofia]] and other major Bulgarian cities, which were heavily bombed by the Allies in the winter of 1943–1944.

On 2 September 1944, as the [[Red Army]] approached the Bulgarian border, a new Bulgarian government came to power and sought peace with the Allies, expelled the few remaining German troops, and declared neutrality. These measures however did not prevent the Soviet Union from declaring war on Bulgaria on 5 September, and on 8 September the Red Army marched into the country, meeting no resistance. This was followed by the [[Bulgarian coup d'état of 1944|coup d'état of 9 September 1944]], which brought a government of the pro-Soviet [[Fatherland Front (Bulgaria)|Fatherland Front]] to power. After this, the Bulgarian army (as part of the Red Army's [[3rd Ukrainian Front]]) fought the Germans in Yugoslavia and Hungary, sustaining numerous casualties. Despite this, the [[Paris Peace Treaties, 1947|Paris Peace Treaty]] treated Bulgaria as one of the defeated countries. Bulgaria was allowed to keep [[Southern Dobruja]], but had to give up all claims to Greek and Yugoslav territory.

=== Independent State of Croatia ===
{{Main|Independent State of Croatia}}
[[File:Adolf Hitler meets Ante Pavelić.1941.jpg|thumb|[[Adolf Hitler]] meeting with NDH leader [[Ante Pavelić]]]]

On 10 April 1941, the so-called [[Independent State of Croatia]] (''Nezavisna Država Hrvatska'', or NDH), an installed German–Italian puppet state, co-signed the Tripartite Pact. The NDH remained a member of the Axis until the end of Second World War, its forces fighting for Germany even after its territory had been overrun by [[Yugoslav Partisans]]. On 16 April 1941, [[Ante Pavelić]], a Croatian nationalist and one of the founders of the [[Ustaše]] (''"Croatian Liberation Movement"''), was proclaimed ''[[Poglavnik]]'' (leader) of the new regime.

Initially the Ustaše had been heavily influenced by Italy. They were actively supported by Mussolini's [[National Fascist Party]] regime in Italy, which gave the movement training grounds to prepare for war against Yugoslavia, as well as accepting Pavelić as an exile and allowing him to reside in Rome. In 1941 during the Italian invasion of Greece, Mussolini requested that Germany invade Yugoslavia to save the Italian forces in Greece. Hitler reluctantly agreed; Yugoslavia was invaded and the NDH was created. Pavelić led a delegation to Rome and offered the crown of the NDH to an Italian prince of the [[House of Savoy]], who was crowned [[Tomislav II]]. The next day, Pavelić signed the Contracts of Rome with Mussolini, ceding [[Dalmatia]] to Italy and fixing the permanent borders between the NDH and Italy. Italian armed forces were allowed to control all of the coastline of the NDH, effectively giving Italy total control of the Adriatic coastline. When the King of Italy ousted Mussolini from power and Italy capitulated, the NDH became completely under German influence.

The platform of the Ustaše movement proclaimed that Croatians had been oppressed by the Serb-dominated Kingdom of Yugoslavia, and that Croatians deserved to have an independent nation after years of domination by foreign empires. The Ustaše perceived Serbs to be racially inferior to Croats and saw them as infiltrators who were occupying Croatian lands. They saw the extermination and expulsion or deportation of Serbs as necessary to racially purify Croatia. While part of Yugoslavia, many [[Croatian nationalism|Croatian nationalists]] violently opposed the Serb-dominated Yugoslav monarchy, and assassinated [[Alexander I of Yugoslavia]], together with the [[Internal Macedonian Revolutionary Organization]]. Ustashe forces fought against communist [[Yugoslav Partisans|Yugoslav Partisan]] guerrilla throughout the war.

The Ustaše regime lacked general support among Croats and never accrued any significant support among the populace.{{sfn|Shepherd|2012|p=78}}<ref name="Israeli">{{cite book |last1=Israeli |first1=Raphael |title=The Death Camps of Croatia: Visions and Revisions, 1941–1945 |date=2017 |publisher=Routledge |isbn=978-1-35148-403-9 |page=45 |url=https://books.google.com/books?id=uxwuDwAAQBAJ&pg=PA45}}</ref> The Ustaše regime was backed by parts of the Croat population that during the [[interwar period]] had felt oppressed in the Serb-led [[Kingdom of Yugoslavia|Yugoslavia]]. Most of the support it had initially gained by creating a Croatian national state was lost because of the brutal practices it used.<ref name="Sindbaek2002">{{cite book|last=Sindbaek|first=Tina|title=Usable History?: Representations of Yugoslavia's Difficult Past from 1945 to 2002|year=2002|publisher=Aarhus University Press|page=27}}</ref>

Upon coming to power, Pavelić formed the [[Croatian Home Guard (World War II)|Croatian Home Guard]] (''Hrvatsko domobranstvo'') as the official military force of the NDH. Originally authorized at 16,000 men, it grew to a peak fighting force of 130,000. The Croatian Home Guard included an air force and navy, although its navy was restricted in size by the Contracts of Rome. In addition to the Croatian Home Guard, Pavelić was also the supreme commander of the [[Ustaše militia]], although all NDH military units were generally under the command of the German or Italian formations in their area of operations.

The Ustaše government declared war on the Soviet Union, signed the Anti-Comintern Pact of 1941, and sent troops to Germany's Eastern Front. Ustaše militia were garrisoned in the Balkans, battling the communist partisans.

The Ustaše government applied racial laws on Serbs, Jews, and [[Romani people]], as well as targeting those opposed to the fascist regime, and after June 1941 deported them to the [[Jasenovac concentration camp]] or to [[Nazi concentration camps]] in Poland. The racial laws were enforced by the Ustaše militia. The exact number of victims of the Ustaše regime is uncertain due to the destruction of documents and varying numbers given by historians. According to the [[United States Holocaust Memorial Museum]] in Washington, D.C., between [[Genocide of Serbs in the Independent State of Croatia|320,000 and 340,000 Serbs were killed in the NDH]].<ref name="US Holocaust Memorial Museum">[https://web.archive.org/web/20030711191159/http://www.ushmm.org/wlc/article.php?lang=en&ModuleId=10005449 Jasenovac] United States Holocaust Memorial Museum web site</ref>

===Yugoslavia (two-day membership)===
{{main|Yugoslav accession to the Tripartite Pact|Yugoslav coup d'état|Invasion of Yugoslavia}}

Yugoslavia was largely surrounded by members of the pact and now bordered the German Reich. From late 1940 Hitler sought a non-aggression pact with Yugoslavia. In February 1941, Hitler called for Yugoslavia's accession to the Tripartite Pact, but the Yugoslav government delayed. In March, divisions of the German army arrived at the Bulgarian-Yugoslav border and permission was sought for them to pass through to attack Greece. On 25 March 1941, fearing that Yugoslavia would be invaded otherwise, the Yugoslav government signed the Tripartite Pact with significant reservations. Unlike other Axis powers, Yugoslavia was not obliged to provide military assistance, nor to provide its territory for Axis to move military forces during the war. Less than two days later, after demonstrations in the streets of Belgrade, [[Prince Paul of Yugoslavia|Prince Paul]] and the government were removed from office by a [[Yugoslav coup d'état|coup d'état]]. Seventeen-year-old [[Peter II of Yugoslavia|King Peter]] was declared to be of age. The new Yugoslav government under General [[Dušan Simović]], refused to ratify Yugoslavia's signing of the Tripartite Pact, and started negotiations with Great Britain and Soviet Union. Winston Churchill commented that "Yugoslavia has found its soul"; however, Hitler invaded and quickly took control.