The Communist Party of Yugoslavia played no part in the coup, although it made a significant contribution to the mass street-protests in many cities that signalled popular support for it once it had occurred.

The putsch was successful and deposed the three-member Yugoslav regency (Prince Paul, Radenko Stanković and Ivo Perović) and the government of Prime Minister Dragiša Cvetković.

The military conspirators brought to power the 17-year-old King Peter II (whom they declared to be of-age to assume the throne) and formed a weak and divided national unity government with Simović as prime minister and Vladko Maček and Slobodan Jovanović as his vice-premiers.

In 1972 military historian Martin van Creveld dismissed the idea, affirming that the invasion of Yugoslavia actually assisted and hastened the overall Balkan campaign, and that other factors determined the start date for Operation Barbarossa.

In particular, the religious primacy of the Serbian Orthodox Church in national affairs and discrimination against Catholics and Muslims compounded the dissatisfaction of the non-Serbian population with the Serbian-dominated ruling groups that controlled patronage and government appointments, and treated non-Serbs as second-class citizens.

The domination of the rest of Yugoslavia by Serbian ruling elites meant that the country was never consolidated in the political sense, and was therefore never able to address the social and economic challenges it faced.

Failures to establish the rule of law, to protect individual rights, to build tolerance and equality, and to guarantee the neutrality of the state in matters relating to religion, language and culture contributed to this illegitimacy and the resulting instability.

[13] With these arrangements in place, Italy posed the biggest problem for Yugoslavia, funding the anti-Yugoslav Internal Macedonian Revolutionary Organisation which promoted Bulgarian irredentism.

[27] The Cvetković-led cabinet formed in the wake of the Agreement was resolutely anti-Axis,[28] but remained on friendly terms with Germany,[17] and included five members of the HSS, with Maček as deputy Prime Minister.

[29] After the outbreak of World War II in September 1939, German pressure on the government resulted in the resignation in mid-1940 of the Minister of the Interior, Stanoje Mihaldžić, who had been organising covert anti-Axis activities.

[35] In early November 1940, following the Italian invasion of Greece, Nedić, stated in a memorandum to Prince Paul and the government, that he believed that Yugoslavia was about to be fully encircled by enemy countries and that ultimately Germany would win the war.

[38] Over the next few months, Prince Paul and his ministers laboured under overwhelming diplomatic pressure, a threat of an attack by the Germans from Bulgarian territory, and the unwillingness of the British to promise practical military support.

[39] Six months prior to the coup, British policy towards the government of Yugoslavia had shifted from acceptance of Yugoslav neutrality to pressuring the country for support in the war against Germany.

[40] On 23 January 1941, William J. Donovan, a special emissary of US President Franklin D. Roosevelt, visited Belgrade and issued an ultimatum, saying that if Yugoslavia permitted German troop passage then the US would not "interfere on her behalf" at peace talks.

[48][49] On 17 March, Prince Paul returned to Berchtesgaden and was told by Hitler that it was his last chance for Yugoslavia to join the Pact, renouncing this time the request for the use of Yugoslav railways in order to facilitate their accession.

[61] On the morning of 27 March, Deputy Prime Minister Maček was informed of the coup and met Prince Paul at Zagreb Central Station to discuss the situation.

Accompanied by Šubašić, he reached the capital by train that evening and was met by Simović, who took him to the war ministry where he and the other two regents relinquished power, immediately abolishing the regency.

[63][62] Having already made arrangements with the British consul in Zagreb, Prince Paul and his family left that evening for Greece, after which they travelled to Kenya, spending time at Oserian and then exile in South Africa.

[73] According to the memoirs of the Serbian Orthodox Patriarch, Gavrilo V, the putsch was immediately welcomed by the senior clergy of the church, as the Holy Assembly of Bishops convened on 27 March in response to the coup.

Archbishop Aloysius Stepinac, president of the Roman Catholic Episcopal Conference of Yugoslavia, bitterly wrote in his diary that, "All in all, Croats and Serbs are of two worlds... that will never move closer to one another without an act of God".

Mirković claimed sole credit immediately after the coup and stated on its tenth anniversary that: "Only after I had informed General [Simović] about my idea and he had accepted it did I make the decision to undertake the planned revolt.

Nedić and Krasojević refused as they felt they could not take an active part due to their positions, Stanković promised not to use the Royal Guard against the people and to keep his knowledge of the plot secret, Ilić did not think he had the political influence to perform the role, and Simović agreed.

[83][84][85] According to the historian Marta Iaremko, writing in 2014, "the vast majority of researchers" consider that the putsch was planned with the assistance of the British intelligence services, but that this, and their encouragement of the revolt, were not sufficient to ensure it was carried out.

[94] On 30 March, Foreign Minister Momčilo Ninčić summoned the German ambassador, Viktor von Heeren, and handed him a statement which declared that the new government would accept all its international obligations, including accession to the Tripartite Pact, as long as the national interests of the country were protected.

Hungary and Bulgaria were promised the Banat and Yugoslav Macedonia respectively and the Romanian army was asked not to take part, holding its position at the Romania-Yugoslav border.

While he considered the coup had been an entirely Serbian initiative aimed at both Prince Paul and the Cvetković–Maček Agreement, he decided that he needed to show HSS support for the new government and that joining it was necessary.

[70][104] That same day exiled Croatian politician and Ustaše leader Ante Pavelić called for Croats to start an uprising against the government over his Radio Velebit program based in Italy.

[115] According to the British major general and historian I. S. O. Playfair, the coup was essentially a brave gesture of defiance, mainly by Serbs, against the German domination signified by signing of the Tripartite Pact, undertaken in the full knowledge that invasion would likely follow.

[94] It was also, according to the historian Alexander Prusin, an "utter blunder, based on wishful thinking and emotions rather than a realistic appreciation of the country's limited economic and military potential".

[123] Sue Onslow, in a bid to place the coup in the broader context of the British policy towards Yugoslavia between the outbreak of the Second World War and the events on 27 March 1941, writes that the coup was a major propaganda victory for Britain, as it "proved a tremendous, if ephemeral, boost to British morale, coming rapidly upon the victories against Italian forces in North Africa and the Sudan"; it also was "a much-needed fillip to the 'upstart'... Special Operations Executive created by [Hugh] Dalton".