The Ten-Day War (Slovene: Desetdnevna vojna), or the Slovenian War of Independence (Slovene: Slovenska osamosvojitvena vojna), was a brief armed conflict that followed Slovenia's declaration of independence from Yugoslavia on 25 June 1991. It was fought between the Slovenian Territorial Defence and the Slovenian National Police Force on one side, and the Yugoslav People's Army (JNA) on the other. It lasted from 27 June 1991 until 7 July 1991, when the Brioni Accords were signed.
It was the second of the Yugoslav Wars to start in 1991, following the Croatian War of Independence in March, and by far the shortest of the conflicts with fewest overall casualties. The war was brief because the JNA, dominated by Serbs and Montenegrins, although still made up of all the nationalities of Yugoslavia, did not want to waste resources on this campaign. Slovenia was considered "ethnically homogeneous" and therefore of no interest to the Yugoslav government. The military was preoccupied with the fighting in Croatia, where the Serb and Montenegrin majority in Yugoslavia had greater territorial interests. In the BBC documentary The Death of Yugoslavia, which used archival footage, Slobodan Milošević, President of Serbia, is recorded stating that "I was against using the Yugoslav Army in Slovenia", while Borisav Jović, President of the Presidency of Yugoslavia, stated that, "With Slovenia out of the way, we could dictate the terms to the Croats."
Background
After the death of Yugoslav president Josip Broz Tito in 1980, underlying political, ethnic, religious, and economic tensions within Yugoslavia surfaced. In 1989 Slobodan Milošević, Chairman of the Central Committee of the League of Communists of Serbia since 1986, became President of Serbia, the largest and most populous of the six Yugoslav republics. Mateja Sednak explains,
As... Milošević moved to consolidate power by centralizing the state, the governments of the other republics sought to loosen the central grip on power by devolving as much constitutional power as possible to each of the republics and autonomous provinces.
A series of disagreements among delegates persisted until four of the six Yugoslav republics each made decisions to seek independence from Yugoslavia. Slovenia was among the republics aiming for independence, and it was subsequently recognised by Germany and the Vatican.
In April 1990, Slovenia held its first democratic multi-party elections, won by the DEMOS coalition.
Preparations for war
On 23 December 1990, Slovenia held a referendum, which passed with 88.5% of overall electorate supporting independence (95.7% of votes cast), with a turnout of 93.3%. The Slovenian government was well aware that the federal government in Belgrade might seek to use military force to quash Slovenia's move towards independence. Immediately after the Slovenian elections, the JNA announced a new defence doctrine that would apply across the country. The Tito-era doctrine of "General People's Defence", in which each republic maintained a territorial defence (TO), was to be replaced by a centrally directed system of defence. The republics would lose their role in defence matters, and their TOs would be disarmed and subordinated to the JNA's headquarters in Belgrade.
The Slovenian government resisted these moves and successfully ensured that the majority of Slovenian Territorial Defence equipment was kept out of the hands of the JNA. It also declared in a constitutional amendment passed on 28 September 1990 that its TO would be under the sole command of the Slovenian government. At the same time, the Slovenian government set up a secret alternative command structure, known as the Manoeuvre Structures of National Protection (Manevrska struktura narodne zaščite, or MSNZ). This was an existing but antiquated institution, unique to Slovenia, which was intended to enable the republic to form an ad hoc defence structure, akin to a home guard. It was of negligible importance prior to 1990, with antiquated weapons and few members. However, the DEMOS-led government realised that the MSNZ could be adapted to provide a parallel organisation to the TO that would be entirely in the hands of the Slovenian government.
When the JNA tried to take control of the Slovenian Territorial Defence, the TO's command structure was simply replaced by that of the parallel MSNZ. Between May and October 1990, some 21,000 Slovenian Territorial Defence and police personnel were secretly mobilised into the MSNZ command structure, of which the federal government was wholly unaware. The Slovenian government also undertook detailed planning of a military campaign against the JNA, which resulted in the production of an operational and tactical plan by November 1990 – over seven months before the conflict actually began.
The Slovenes were aware that they would not be able to deter the JNA's forces for an extended period of time. Under Defence Minister Janez Janša, they adopted a strategy based on an asymmetric warfare approach. TO units would carry out a guerrilla campaign, using anti-tank weapons and anti-aircraft missiles to ambush the JNA's units. Tank columns could be trapped by destroying the lead and rear vehicles in favourable terrain – for instance, on a narrow mountain road where room for manoeuvre was limited – enabling the rest to be dealt with more easily. In preparation for this, the Slovenian government covertly bought lightweight missile systems from foreign suppliers, notably the SA-7 Grail (Strela) anti-aircraft missile and the German-designed Armbrust anti-tank system. Hit-and-run and delaying tactics were to be preferred and frontal clashes were to be avoided since in such situations the JNA's superior firepower would have been very difficult to overcome.
Conflict
Slovenia and Croatia passed their acts of independence on 25 June 1991. This "advance" on the date of independence was a critical element of the Slovenian plan to gain an early advantage in the expected conflict. The Slovenian government fully expected the Yugoslav military to respond with force on the day of the declaration of independence or shortly afterwards. By secretly advancing the date by 24 hours, the Slovenians caught the Yugoslav government off guard, which had set 26 June as the date for its move.
Although the JNA was adamantly opposed to Slovenian independence, it was divided about what to do. The JNA Chief of Staff, Colonel-General Blagoje Adžić, advocated a large-scale military operation to remove the Slovenian government and bring "healthy forces" to power in the republic. His political superior, the Yugoslav defence minister, General of the Army Veljko Kadijević, insisted on a more cautious approach – essentially a show of force that would convince the Slovenian government to back down on its declaration of independence. After some debate, Kadijević got his way.
It is unclear how much the civilian members of the Yugoslav government were involved in the decision to resort to force in Slovenia. Ante Marković, the president of the Federal Executive Council (equivalent to prime minister) is reported to have said that the federal government had not been informed of the Army's actions.
26 June 1991
On the morning of 26 June, units of the JNA's 13th Corps left their barracks in Rijeka, Croatia, to move towards Slovenia's borders with Italy. The move immediately led to a strong reaction from local Slovenians, who organized spontaneous barricades and demonstrations against the JNA's actions.
By this time, the Slovenian government had already put into action its plan to seize control of the republic's border posts and the international airport at Brnik. The personnel manning the border posts were, in most cases, already Slovenians, so the Slovenian take-over mostly simply amounted to changing of uniforms and insignia, without any fighting. This was undertaken, in the words of Janez Janša, to "establish our sovereignty in the key triangle, border-customs-air control". It also had important practical effects. The border crossings were a major source of revenue. In addition, by taking control of the borders, the Slovenians were able to establish defensive positions against an expected JNA attack. This meant that the JNA would have to fire the first shot. It was fired on 26 June at 14:30 in Divača by an officer of the JNA.
27 June 1991
Further JNA troop movements took place in the early hours of 27 June. A unit of the JNA's 306th Anti-Aircraft Regiment, based in Karlovac, Croatia, crossed the Slovenian border at Metlika. A few hours later, a column of tanks and armoured personnel carriers of the JNA 1st Armoured Brigade left their barracks at Vrhnika near Ljubljana, heading for the airport at Brnik. They arrived a few hours later and took control of the facilities. As the JNA was the federal army, its forces were customarily deployed in various places within the federal republics including Slovenia. To the east, JNA units left Maribor heading for the nearby border crossing at Šentilj and the border town of Dravograd further west. The Yugoslav Air Force aircraft dropped leaflets over various parts of Slovenia bearing the messages "We invite you to peace and cooperation!" and "All resistance will be crushed."
In the early hours of 27 June the Slovenian leadership was told of the movements of the JNA. The military leadership of the Fifth Military District, which included Slovenia, was in telephone contact with Slovenian president Milan Kučan, telling him that the troops' mission was limited to taking over the border crossings and airport. A meeting of the Slovene presidency was hastily convened at which Kučan and the rest of the members decided on armed resistance.
The Slovenian government had received warnings that the JNA would use helicopters to ferry special forces troops to strategic locations. It issued a warning to the JNA's 5th Military Command District in Zagreb that if helicopters continued to be used they would be shot down. The warning was disregarded by the JNA leadership, which still believed that the Slovenians would back down rather than fight. This was, however, a disastrous miscalculation. In the afternoon of 27 June, the Slovenian TO shot down two JNA helicopters with SA-7 missiles, one of them a Gazelle over Rožna Dolina, Ljubljana, killing the occupants, one of whom, Toni Mrlak, was a Slovenian pilot, as the JNA's forces consisted of nationals from all the republics. It was later discovered that the Gazelle which Mrlak had been flying was unarmed, and was carrying only bread for the Yugoslav soldiers.
The Slovenian TO also took up positions around JNA barracks in various locations, effectively besieging them, and launched a series of attacks on JNA forces across Slovenia. At Brnik, a Slovenian TO unit attacked the JNA troops holding the airport, and at Trzin a firefight developed in which four JNA soldiers and one Slovenian TO soldier (Edvard Peperko) were killed and the remainder of the JNA unit was forced to surrender. Attacks were also launched by Slovenian TO units on JNA tank columns at Pesnica, Ormož and Koseze near Ilirska Bistrica. A tank column from the JNA's 32nd Mechanised Brigade, advancing from Varaždin in Croatia, was blocked at Ormož near the Slovenian border and found itself unable to break through a Slovenian barricade.
Despite the confusion and fighting, the JNA nonetheless successfully accomplished much of its military mission. By midnight on 27 June it had captured all of the crossings along the Italian border, all but three crossings on the Austrian border and several of the new crossing points established along Slovenia's border with Croatia. However, many of its units were still stuck in vulnerable positions across Slovenia.
28 June 1991
During the night of 27–28 June, Slovenian TO units were ordered to undertake a general offensive against the JNA. The Slovenian defence ministry ordered:
At all locations where RS (Republic of Slovenia) armed forces (Slovenian Territorial Defence) have the tactical advantage, offensive actions against enemy units and facilities will be carried out. The enemy will be summoned to surrender, the shortest deadline possible for surrender given and action taken using all available weapons. While in action, any necessary arrangements will be made to evacuate and protect the civilians.
Additional fighting took place throughout the day. The JNA tank column that had been attacked at Pesnica the previous day was blocked by impromptu barricades of Slovenian trucks at Štrihovec, a few kilometres short of the border with Austria, where it again came under attack by Slovenian TO personnel and Slovenian police. The Yugoslav Air Force mounted two airstrikes in support of the JNA forces at Strihovec, killing four truck drivers. At Medvedjek in central Slovenia, another JNA tank column came under attack at a truck barricade, where air raids killed six truck drivers.