Operation Storm

Operation Storm (Serbo-Croatian: Operacija Oluja / Операција Олуја) was the last major battle of the Croatian War of Independence and a major factor in the outcome of the Bosnian War. It was a decisive victory for the Croatian Army (HV), which attacked across a 630-kilometre (390 mi) front against the self-declared proto-state Republic of Serbian Krajina (RSK), and a strategic victory for the Army of the Republic of Bosnia and Herzegovina (ARBiH). The HV was supported by the Croatian special police advancing from the Velebit Mountain, and the ARBiH located in the Bihać pocket, in the Army of the Republic of Serbian Krajina's (ARSK) rear. The battle, launched to restore Croatian control of 10,400 square kilometres (4,000 square miles) of territory - representing 18.4% of the territory it claimed - and Bosniak control of Western Bosnia, was the largest land battle that took place in Europe between the end of World War II and the 2022 Russian invasion of Ukraine. Operation Storm commenced at dawn on 4 August 1995 and was declared complete on the evening of 7 August, despite significant mopping-up operations against pockets of resistance lasting until 14 August.

Operation Storm was a strategic victory in the Bosnian War, effectively ending the siege of Bihać and placing the HV, Croatian Defence Council (HVO), and the ARBiH in a position to change the military balance of power in Bosnia and Herzegovina through the subsequent Operation Mistral 2. The operation was conceived on HV and HVO advances made during Operation Summer '95, when strategic positions allowing the rapid capture of the RSK capital Knin were gained, and on the continued arming and training of the HV since the beginning of the Croatian War of Independence, when the RSK was created during the Serb Log Revolution and Yugoslav People's Army intervention. The operation itself followed an unsuccessful United Nations (UN) peacekeeping mission and diplomatic efforts to settle the conflict.

The HV's and ARBiH's strategic success was a result of a series of improvements to the armies themselves, and crucial breakthroughs made in the ARSK positions that were subsequently exploited by the HV and the ARBiH. The attack was not immediately successful at all points, but seizing key positions led to the collapse of the ARSK command structure and overall defensive capability. The HV capture of Bosansko Grahovo, just before the operation, and the special police's advance to Gračac, made it nearly impossible to defend Knin. In Lika, two guard brigades quickly cut the ARSK-held area, which lacked tactical depth and mobile reserve forces, and they isolated pockets of resistance, positioned a mobile force for a decisive northward thrust into the Karlovac Corps area of responsibility (AOR), and pushed ARSK towards Banovina. The defeat of the ARSK at Glina and Petrinja, after a tough defensive, defeated the ARSK Banija Corps as well, since its reserve was pinned down by the ARBiH. The RSK relied on the Republika Srpska and Yugoslav militaries as its strategic reserve, but they did not intervene in the battle. The United States also played a role in the operation by directing Croatia to a military consultancy firm, Military Professional Resources Incorporated (MPRI), that signed a Pentagon-licensed contract to advise, train, and provide intelligence to the Croatian army.

The HV and the special police suffered 174–211 killed or missing, while the ARSK had 560 soldiers killed. Four UN peacekeepers were also killed. The HV captured 4,000 prisoners of war. The number of Serb civilian deaths is disputed—Croatia claims that 214 were killed, while Serbian sources cite 1,192 civilians killed or missing. The Croatian population had been years prior subjected to ethnic cleansing in the areas held by ARSK by rebel Serb forces, with an estimated 170,000–250,000 expelled and hundreds killed. During and after the offensive, around 150,000–200,000 Serbs of the area formerly held by the ARSK had fled, and a variety of crimes were committed against some of the remaining civilians there by Croatian forces. On 4 August, RSK authorities ordered the evacuation of the population in the Northern Dalmatia and Lika areas, followed by Glina and Vrginmost on 6 August. The Croatian Serb population who fled formed one of the largest refugee populations in Europe.

The International Criminal Tribunal for the Former Yugoslavia (ICTY) later tried three Croatian generals charged with war crimes and partaking in a joint criminal enterprise designed to force the Serb population out of Croatia, although all three were ultimately acquitted, and the tribunal refuted charges of a criminal enterprise. The ICTY concluded that Operation Storm was not aimed at ethnic persecution, as civilians had not been deliberately targeted. The ICTY stated that the Croatian Army and Special Police committed a large number of crimes against the Serb population after the artillery assault, but that the state and military leadership were not responsible for their creation and organization, and that Croatia did not have the specific intent of displacing the country's Serb minority. However, Croatia adopted discriminatory measures to make it increasingly difficult for Serbs to return. Human Rights Watch reported that the vast majority of the abuses during the operation were committed by Croatian forces and that the abuses continued on a large scale for months afterwards, which included summary executions of Serb civilians and the burning and destruction of Serb property. In 2010, Serbia filed a counterclaim against Croatia before the International Court of Justice (ICJ), claiming that the offensive constituted a genocide. In 2015, the court ruled that neither Serbia nor Croatia proved sufficient evidence that either side committed genocide, thereby dismissing both cases.

A crisis emerged in Yugoslavia with the weakening of the communist states in Eastern Europe towards the end of the Cold War. In Croatia, the regional branch of the League of Communists of Yugoslavia, the League of Communists of Croatia, had lost its ideological potency. The Republics of Slovenia and Croatia advocated decentralization. SR Serbia, headed by Slobodan Milošević, adhered to centralism and single-party rule. After a series of street protests dubbed anti-bureaucratic revolutions by his supporters in 1988-89 succeeded in overthrowing the government of the Socialist Republic of Montenegro, as well as the governments of the Serbian autonomous provinces of Vojvodina and Kosovo, replacing their leaders with Milošević allies, Croatia and Slovenia turned against him.

On 8 July 1989, a large Serb nationalist rally was held in Knin, during which banners threatening Yugoslav People's Army (JNA) intervention in Croatia, as well as Chetnik iconography, were displayed. During World War II in Yugoslavia, they operated as "legalised" auxiliary forces under Axis control, and most historians who have considered the question regard the Chetnik crimes against Muslims and Croats during this period as constituting genocide. In the autumn of 1989, the Serbian government pressured the Croatian government to allow a series of Serb nationalist rallies in the country. The Serbian media and various Serbian intellectuals had already begun to refer to the Croatian leadership as "Ustaše", and began to make reference to genocide and other crimes committed by the Ustaše between 1941 and 1945. The Serbian political leadership approved of the rhetoric and accused the Croatian leadership of being "blindly nationalistic" when it objected. On 4 March 1990, 50,000 Serbs rallied at Petrova Gora and shouted negative remarks aimed at Franjo Tuđman, chanted "This is Serbia", and expressed support for Milošević. Tuđman came to prominence as a pro-Independence dissident, and his leadership was partially founded on an anti-Serb rhetoric and symbols.

In April–May 1990, Tuđman's right-wing, pro-independence Croatian Democratic Union (HDZ) triumphed in Croatia's first multi-party elections. The HDZ's election victory caused consternation amongst much of the Croatian Serb population, who likened the resurgence of Croatian nationalism to the return of the fascist Ustaše regime, which ruled the Axis puppet state known as the Independent State of Croatia during World War II. This, in turn, fed a rise in Serbian nationalism in many Croatian Serb communities, which was encouraged by the government of the Socialist Republic of Serbia, led by Milošević. Prominent members of the RSK government, including Milan Babić and Milan Martić, later testified that Belgrade directed a propaganda campaign portraying the Serbs in Croatia as being threatened with genocide by the Croat majority. The HDZ-led government promoted a traditionalist and exclusive vision of Croatia as a Croat state in which Serbs were unwelcome. Many Serbs were removed from the bureaucracies and the police and replaced by ethnic Croats, bilingual road signs were torn down even in Serb-majority areas, and Ustaše symbols were sometimes restored.