- May 1941 – Jadovno camp set up, as the place to collect and kill the prisoners, mostly Jews and Serbs
- August 1941 – following the Italian re-occupation of the area, Jadovno ceases to be in operation
- 1988 – the monument to the Jadovno camp victims unveiled. The monument was destroyed in 1991 during the war in Croatia, and restored in 2011
The Velebit-Gospic-Pag camp system was created by Eugen Dido Kvaternik. He started working on it in the early days of June 1941, immediately after his return from Berlin, where he had discussions in the SS Headquarters. The Velebit-Gospic-Pag camp system was under the direct jurisdiction of the municipal operational police administration in Gospic. Dido Kvaternik appointed Stephen Rubinic as the governor and, on 18 June, he sent him from Zagreb to Gospic with an order that to establish a camp in Jadovno and exercise temporary control of the camp in Pag. The location in Jadovno was chosen by Jurica Frkovic, the first Ustasha Commissioner for Lika and the county prefect of Gacko and Lika and Juco Rukavina, the first commander of the Ustasha Militia who were very familiar with the locations on Velebit mountain, being locals and participants in the 1932 Velebit Uprising.
The Jadovno village lies in a Velebit’s thick forest, on a 1500 m long clearing, at 805 metres above sea level, 16 kilometres northwest of Gospic. The camp itself was located deep in the Velebit forest, at an altitude of 1,200 meters, 6.5 kilometres from the nearest village of Jadovno, in inaccessible terrain on the 90x180 meter clearing called Cacic dolac. The camp was fully isolated and, unlike other camps in the Independent State of Croatia (ISC), not a single package had ever arrived to Jadovno nor had anyone ever received any letter from it. Although the Jewish Community in Zagreb repeatedly tried to deliver packages and even received a permission from the ISC authorities to do that, no packages had ever arrived in Jadovno. The isolation of the camp was complete and no one had ever had any access to it except for high-ranking Ustashi.
The main collection and transit centre for the Jadovno camp was the old penitentiary of the Gospic court. It usually held between 2,000 and 4,000 prisoners. Interrogations, accompanied by various forms of torture took place in the penitentiary. The fate of the prisoners was decided there: straight to death or to a camp on the island of Pag, in Jadovno or Ovcara - a former farm near Gospic converted to a concentration and labour camp. The prisoners who were assigned to Pag would be taken by truck to Baske Ostarije or Karlobag, where they would be taken over by members of 13th Ustasha Battalion commanded by Ustasha Ivan Devcic Pivac, who were was in charge of the Slana and Metajna camps on the island of Pag. There were also prisoners who had to walk from Gospic through Baske Ostarije to Karlobag. Few of them managed to reach Karlobag, since many had been murdered on the way and thrown into pits in Velebit. Prisoners who were being transferred from the penitentiary to Jadovno would usually be taken by trucks to the village of Trnovac, from where they had to walk 12.5 kilometres to the Jadovno camp. The prisoners often had to walk the entire 23.5 kilometre route from Gospic to the Jadovno camp while being subjected to physical abuse. There are testimonies to that from witnesses who lived in the villages under Velebit who saw the prisoners (poorly or well dressed) going in columns to Jadovno almost every day in the summer of 1941.
The first prisoners to arrive in Jadovno on 24 June 1941 were the Jews from Zagreb. About 200 of them were brought from Zagreb to Gospic. Some 30 of them were taken from the Gospic penitentiary to the Cacic Dolac area of Velebit. Their main task was to enclose the area using barbed wire. Larger groups started arriving after a few days. There were two barracks for the Ustasha guards, while the prisoners slept rough in the first days. It was only later that they were allowed to build shelters covered with fir and ferns each of which, according to Djuro Zatezalo’s research, could accommodate between 20 and 30 people. The prisoners were divided by nationality: the Jews, the Serbs, and the few Croats. The Jews were located in the western part of the camp which was 50 meters long, the Serbs in the northern and the southern part of the camp, covering a distance of 130 meters, and the Croats next to the Serbs in an area that was 20 meters long. The camp’s area dimensions were 170x90 meters, surrounded by a double row of barbed wire that could reach as high as four metres. All the remaining money and possessions were seized at the entrance to the camp. Researcher Franjo Zdunić Lav counted exactly 55 prisoners who had been released or transferred to other camps before the liquidation of the Jadovno camp: 31 Croatian prisoners (10 of whom were released and 21 transferred to other camps), 10 young Jewish men from Zagreb whom lieutenant Janko Mihalovic, their classmate, pulled out of the camp to sweep the streets of Gospic, three of whom survived the war as partisans, five Serbs from the surrounding villages under Velebit who managed to escape and about a dozen prisoners who were released following an intervention. Jadovno camp existed for about two months, and the life in it was based on exhausting work. The food was miserable, some beans and hot gruel, once a day. The nights were unbearable due to the damp forest and very low temperatures. After two successful escape attempts and an unsuccessful one, works outside the wire fence were abolished and the prisoners were left to a cruel fate by working on meaningless tasks that only led to even greater exhaustion and the feeling of helplessness.
The capacity of the camp was between 1,500 and 2,000 prisoners. In July 1941, the camp was overcrowded and numbered about 3,000 prisoners. Prisoners used to arrive to the Jadovno camp from various parts of the then ISC (from eastern Bosnia to Zagorje in Croatia). The prisoners were being executed outside the camp, most likely by the pit under Grgin brijeg (about 1.5 kilometres from the camp), but also in other nearby caves and sinkholes. Soon after the arrival of 165 young Zagreb Jews from Danica, the Ustashi threw 155 of them into the pit at Grgin brijeg. After they had been thrown into the pit tied by wire, the Ustasha would throw grenades at them. 73 Orthodox priests – one in three Serbian Orthodox Church priests killed in its territory of ISC was killed in the Jadovno killing fields. The bones of Sava Trlajic, Bishop of Karlovac and Petar Zimonjic, Metropolitan of Sarajevo, whom the Ustashi had tortured in a particularly brutal way, lie in the unmarked pits. The exhumation and the burial of the victims has never taken place.
Djuro Zatezalo estimated the number of victims to at least 40,123. 32,103 of them were killed in Jadovno, and 8,020 in the area of Slana and Metajna. According to Zatezalo, 38,010 of them were Serbs, 1,998 Jews, 88 Croats, 11 Slovenians, nine Muslims, two Hungarians, two Czechs, one Russian, one Roma and one Montenegrin. On the name list of the Jadovno camp victims Zatezalo managed to count 10,502 victims. Out of the 10,502 listed 9,663 were Serbs, 762 Jews, 55 Croats, 9 Muslims, 8 Slovenians, one Hungarian, one Czech, one Russian, one Roma and one Montenegrin. Franjo Zdunić Lav, a resident of Gospic in 1941, in his book "The Gospic District and the Perusic District in the 1941-1945 National Liberation War", based on what he knew and assessed, says that over 37,000 people were killed in the Jadovno-Velebit -Pag camp complex. In the book "The Ustasha and the Independent State of Croatia" Fikret Jelic Butic writes mentions a figure of about 30,000 to 48,000 killed, while Ljubo Boban quotes the statement from the Military Encyclopaedia of Yugoslavia saying that a total of 72,000 people were killed in the camp, and as many as 35,000 at Saranova jama. Dragan Cvetkovic from the Museum of Genocide Victims provides the information that between 15,300 and 15,900 people were killed in Jadovno, of whom 1800 to 2000 Jews and 13,400 -13,800 Serbs. Ivo Goldstein believes that the figure of 28,700 arrested as Ilija Jakovljevic heard from Stjepan Rubinic at the time of his imprisonment in Stara Gradiska halfway through the war is the one closest to the truth. When we subtract 4,000 people who left Gospic in late August after the disbanding of the camp, then the figure of 24,000 people who went missing on Velebit, Pag and in Gospic is closest to the truth. Among them were at least 2,500 Jews from throughout the ISC territory.