During World War II, the Croatian Peasant Party (Hrvatska seljačka stranka, HSS) splintered into several factions pursuing different policies and alliances. Prior to the German invasion of Yugoslavia, it was the most powerful political party among ethnic Croats, controlled the administration and police in Banovina of Croatia, and commanded two paramilitary organisations. After the successful invasion of the Kingdom of Yugoslavia in April 1941, Nazi Germany proposed that HSS leader Vladko Maček could rule Croatia as a puppet state. He declined, but the Ustaše agreed and proclaimed the Independent State of Croatia (Nezavisna država Hrvatska, NDH). Under duress, Maček called on Croats to support the regime. A splinter of the HSS and all HSS-controlled infrastructure went over to the Ustaše.
The Communist Party of Yugoslavia (KPJ) and its nominally independent branch, the Communist Party of Croatia (KPH) established the Yugoslav Partisans as armed resistance against the NDH. Maček believed that the Western Allies would prevail and would not allow a Communist regime to be established in Yugoslavia. Consequently, he preferred to wait until a favourable moment to return to power, while maintaining distance from both the Ustaše and the Communists. Another group of HSS members opposed this strategy and broke with the party to cooperate with the KPH and join the Partisans. The KPH welcomed the HSS faction while working to sever ties between the HSS members within Partisan ranks and Maček.
The faction loyal to Maček plotted to take over the NDH's regular army – the Croatian Home Guard, assuming support from Home Guards officers who supported an alliance with the Western Allies. The plotters expected an Allied landing in Dalmatia, which they intended to use to negotiate as an equal party and prevent the establishment of a Communist regime in Yugoslavia after the war. The scheme failed because the United Kingdom had already decided to support the Partisans. In response, the Maček faction tried to negotiate directly with the KPH, but the talks broke down. Instead, the British helped strike the Vis Agreement between the KPJ and Partisan leader Josip Broz Tito and the Yugoslav government-in-exile led by HSS member and former Ban of Croatia Ivan Šubašić, providing for power-sharing between the KPJ and prewar democratic parties.
At the end of the war, the provisional coalition government came under control of the KPJ and the non-Communist ministers resigned before the 1945 Yugoslavian parliamentary election, which was boycotted by the non-Communist opposition. Maček fled Yugoslavia and continued political work from abroad, while the HSS was suppressed in the country and became inactive by 1948.
Background
The Croatian Peasant Party (Hrvatska seljačka stranka, HSS) was the main political party of Croats in the Kingdom of Yugoslavia. The HSS was persecuted by Yugoslav authorities due to the party's opposition to political unitarism advocated by the government. Prompted by the failure of the government to secure the rule of law and public order, the HSS established the (HSZ) as a party paramilitary force in 1936. The force was established to protect Croats against paramilitaries supported or tolerated by the regime. The force was also designed as a response to Ustaše challenge for dominance among Croats as a force capable of providing physical protection following the Velebit uprising. It was meant to demonstrate that the HSS is not a pacifist organisation resigned to passivity. In cities, the HSZ operated under the name of Croatian Civil Defence.
Invasion of Yugoslavia
Following the 1939 German invasion of Poland, the Cvetković–Maček government declared its neutrality. After the Axis Tripartite Pact was joined by neighboring countries of Hungary, Romania on 20 and 23 November 1940 respectively, and by Bulgaria on 1 March 1941, Yugoslavia followed their example on 25 March 1941 and joined the alliance. Two days later, the government was overthrown and replaced by a new one led by General Dušan Simović who withdrew Yugoslavia from the Tripartite Pact. Aiming to improve support for his cabinet among ethnic Croats, Simović continued to cooperate with the HSS and expanded the authority of Banovina of Croatia to include the police and armed forces. As a result, the president of the HSS and deputy prime minister of Yugoslavia Vladko Maček to consider disbanding HSS paramilitaries. At the time, the HSS was the most popular political party in Croatia, and the party's ideology included commitment to pacifism.
In retribution for Yugoslavia's withdrawal from the Tripartite Pact, German dictator Adolf Hitler planned to partition the country and annex parts of its territory to Nazi Germany and its allies. Italian dictator Benito Mussolini supported this as he wanted to annex parts of Yugoslavia to Fascist Italy. The German plans for the breakup of Yugoslavia also envisaged some form of autonomy for Croats to exploit Croatian dissatisfaction with Yugoslav rule. Hitler offered Hungary the opportunity to absorb Croatia on 27 March 1941, apparently referring to the territories largely corresponding with the former Kingdom of Croatia-Slavonia, but Regent Miklós Horthy declined the offer. Days later, Germany decided to establish a Croatian puppet state.
Establishment of the Independent State of Croatia
Hitler sought the advice of Alfred Rosenberg, the foreign policy advisor of the Nazi Party, on the establishment of a Croatian state. Rosenberg advised Hitler to offer Maček the leadership of such a state. The German delegation sent to Maček consisted of Foreign Minister Joachim von Ribbentrop's representatives , SS Colonel Edmund Veesenmayer, and Alfred Freundt, the German consul in Zagreb. Maček declined the offer, and the position was reluctantly offered to the Italy-based Ustaše and their leader Ante Pavelić. On 8 April, Maček issued a statement urging order and discipline in the armed forces, without explicitly referencing Yugoslavia.
The Independent State of Croatia (Nezavisna Država Hrvatska, NDH) was declared on 10 April by former Austro-Hungarian Army Lieutenant Colonel and the leader of Ustaše in the country Slavko Kvaternik on the urging of Veesenmayer, as the German Army was approaching Zagreb. Maček issued another statement, made under duress, the same day calling for sincere cooperation with the new "nationalist movement" government. The statement delivered a significant part of the administration and police to the Ustaše virtually intact. Lightly armed HSS militias—the Peasant Guards and the Civic Guards—switched allegiance to the NDH, and several units helped disarm parts of the Royal Yugoslav Army. After the Ustaše established control, some of the militia units were absorbed by NDH armed forces, and others disbanded.
Maček thought the war was between major powers, and that "small [peoples] must shelter under a table". His policy was to wait for the Western Allies to liberate the country so the HSS could continue its work. Maček expected that the Soviet Union would be devastated to a degree where it could not control the post-war settlement and that the Western Allies would not tolerate a Communist regime in post-war Yugoslavia. He expected the country to be restored and expanded territorially and that Croatia would also gain territory. On 11 April, Maček moved to his estate in the village of Kupinec near Zagreb. Yugoslavia surrendered by the end of April, and King Peter II of Yugoslavia and the government fled the country. The decision to abandon organised armed resistance to the Axis powers left the Yugoslav government-in-exile in a weak position, a situation exacerbated by quarreling ministers who appeared united only in their anti-Communism. Maček's decision to resign his ministerial position, with the HSS secretary Juraj Krnjević taking his place, was resented by Serb ministers because it further reduced the prestige of the government. Two other HSS government ministers and close associates of Maček, Ivan Andres and Bariša Smoljan, also resigned their posts to remain in the country.
Armed resistance
With the Yugoslav defeat imminent, the Communist Party of Yugoslavia (Komunistička partija Jugoslavije, KPJ) instructed its 8,000 members to stockpile weapons in anticipation of armed resistance, which would spread, by the end of 1941 to all areas of the country except Vardar Macedonia. Building on its experience in clandestine operations across the country, the KPJ proceeded to organise the Yugoslav Partisans, as resistance fighters led by Josip Broz Tito. The KPJ believed that the German invasion of the Soviet Union had created favourable conditions for an uprising and its politburo founded the Supreme Headquarters of the Partisans with Tito as commander-in-chief on 27 June 1941. In the territory largely corresponding with the present-day Croatia, the Communist Party of Croatia (Komunistička partija Hrvatske, KPH) operated as a nominally independent party with 4000 members at the beginning of the war.
Fracturing of the party Maček's arrest
The HSS split into different factions in 1941. Maček led the most influential faction of the party, which adopted the policy of passively waiting for liberation by the Western Allies and maintaining equal distance from both Ustaše and the KPJ-led Partisans. Other prominent HSS politicians adopted different approaches. A group including former Ban of Croatia Ivan Šubašić fled the country and joined the royal Yugoslav government-in-exile.
Another faction led by Janko Tortić and Marko Lamešić, who signed a resolution declaring the end of Yugoslavia and asking for German help, split off to support the Ustaše. At the local level, around 70 out of 7,000 HSS basic organisations switched allegiance to the NDH. In addition to fracturing of its leadership, the HSS's internal structure was formally disbanded after the NDH banned the party in June 1941. The effort to absorb the (former) HSS members into the Ustaše peaked on 10 August, when 126 HSS party members announced that they were joining the Ustaše. The Ustaše had encouraged their supporters to join and subvert the HSS from within since the August 1939 Cvetković–Maček Agreement allowing the HSS to join the Yugoslav cabinet. The Ustaše opposed any cooperation with the Yugoslav government and declared that Maček was a traitor. His position deteriorated when an envoy of the Plenipotentiary General to the NDH Edmund Glaise-Horstenau visited him in Kupinec in late summer or early autumn to see if he would replace Pavelić. Afraid that Germany or Italy would install Maček as head of the NDH or, alternately, Maček declaring his opposition to the NDH regime, the Ustaše ordered that Maček be taken to the Jasenovac concentration camp on 15 October. His imprisonment virtually ended defections of HSS supporters to the Ustaše movement.
The Ustaše convened the Sabor (the Croatian Parliament) on 23 February 1942 to expand support for the regime and declare the NDH to be a continuation of Croatian statehood. The assembly members were not elected. Invitations to attend were sent to, among others, HSS founders and lifetime members of the HSS general committee, all members of the Croatian Sabor sitting in 1918 and all Yugoslav parliament members elected in 1938 unless they "erred against the advancement of the NDH or the honour or reputation of the Croatian people". The invitations were sent to 93 HSS members, 60 of whom accepted. Some of the respondents thought participation might secure a more stable political environment or improve the HSS' position. A letter was sent to the NDH government by 39 of them protesting Maček's arrest. In March, Maček was moved from Jasenovac back to his estate in Kupinec where he was placed under house arrest. There he maintained intermittent secret contacts with deputy president of the HSS August Košutić and several other party leaders.
Magovac's faction