7th Army (Kingdom of Yugoslavia)

The 7th Army was a Royal Yugoslav Army formation commanded by Divizijski General Dušan Trifunović during the German-led Axis invasion of the Kingdom of Yugoslavia in April 1941 during World War II. It consisted of two divisions, one divisional-strength mountain detachment, one brigade-strength mountain detachment and a brigade-strength infantry detachment. It formed part of the 1st Army Group, and was responsible for the defence of the northwestern border with Italy and the Third Reich.

On 6 April, the Germans seized several mountain passes and bridges over the Drava river. Slovene politicians formed a National Council of Slovenia with the intent of separating from Yugoslavia, and on the right flank of the 7th Army, the 4th Army was seriously weakened by Croat fifth column activities within its major units and higher headquarters from the outset. This alarmed Trifunović, but he was not permitted to withdraw from the border areas until the night of 7/8 April, and this was followed by the German capture of Maribor as they continued to expand their bridgeheads. Italian offensive operations then began, with thrusts towards Ljubljana and down the Adriatic coast, capturing over 30,000 Yugoslav troops near Delnice. On 10 April, the German 14th Panzer Division captured Zagreb, and on 12 April it linked up with the Italians near the Adriatic coast, encircling the remnants of the 7th Army. When fifth column elements arrested the staffs of 1st Army Group, 4th Army and 7th Army at Petrinja those formations effectively ceased to exist. The Yugoslav High Command unconditionally surrendered on 18 April.

Composition
The 7th Army was commanded by Divizijski General Dušan Trifunović, and his chief of staff was Pukovnik Vladimir Petrović. It was organised and mobilised on a geographic basis from the 7th Army District, which was divided into divisional districts, each of which was subdivided into regimental regions. The 7th Army consisted of:
 * 32nd Infantry Division Triglavski
 * 38th Infantry Division Dravska
 * Mountain Detachment Triglavski (divisional-strength)
 * Mountain Detachment Rišnajaski (brigade-strength)
 * Infantry Detachment Lika (brigade-strength)

It was supported by the 71st Army Artillery Regiment, the 7th Anti-Aircraft Battalion, and the motorised 7th Army Anti-Aircraft Company. The 6th Air Reconnaissance Group comprising sixteen Breguet 19s was attached from the Royal Yugoslav Air Force and was based at Cerklje near Brežice.

Deployment
The 7th Army was part of the 1st Army Group, which was responsible for the defence of northwestern Yugoslavia, with the 7th Army along the Reich and Italian borders, and the 4th Army defending the western sector along the Hungarian border. The 1st Cavalry Division was to be held as the 1st Army Group reserve around Zagreb. On the left of the 7th Army was the Adriatic coast, and the boundary with the 4th Army on the right flank ran from Radgon on the Mura through Krapina and Karlovac to Otočac. The Yugoslav defence plan saw the 7th Army deployed in a cordon along the border region from the Julian Alps in the west to Radgon in the east. Of the formations of the 7th Army, the mobilisation of the three detachments was largely complete, but the two divisions had only commenced mobilisation. All 7th Army formations were to be deployed in a cordon, although each formation created a second line of defence from its own troops. The planned deployment of the 7th Army from west to east was:
 * Infantry Detachment Lika on the upper Adriatic coast between Crikvenica and Senj
 * Mountain Detachment Rišnajaski around Delnice in the mountainous Gorski kotar region
 * 32nd Infantry Division Triglavski in the Julian Alps between Ljubljana in the north and Čabar in the south
 * Mountain Detachment Triglavski northwest of Ljubljana around Kranj
 * 38th Infantry Division Dravska in the Pohorje mountains along the Reich border between Dravograd and Maribor

Operations
The border between the Reich and Yugoslavia was unsuitable for motorised operations. Due to the short notice of the invasion, the elements of the invading German 2nd Army that would make up LI Infantry Corps and XLIX Mountain Corps had to be assembled from France, Germany and the Slovak Republic, and nearly all encountered difficulties in reaching their assembly areas. In the interim, the Germans formed a special force under the code name Feuerzauber (Magic Fire). This force was initially intended to merely reinforce the 538th Frontier Guard Division, who were manning the border. On the evening of 5 April, one of the aggressive Feuerzauber detachment commanders, Hauptmann Palten led his Kampfgruppe Palten across the Mura from Spielfeld and, having secured the bridge, began attacking bunkers and other Yugoslav positions on the high ground, and sent patrols deep into the Yugoslav border fortification system. Due to a lack of Yugoslav counter-attacks, many of these positions remained in German hands into 6 April. LI Infantry Corps were tasked with attacking towards Maribor then driving towards Zagreb, while the XLIX Mountain Corps was to capture Dravograd then force a crossing on the Sava. On the first day of the invasion, LI Infantry Corps captured the Drava bridges at Mureck and Radkersburg (opposite Radgon) undamaged, and the 183rd Infantry Division captured 300 prisoners. A bicycle-mounted detachment of the 183rd Infantry Division reached Murska Sobota without striking any resistance. The 132nd Infantry Division also pushed south along the Sejanski valley towards Savci.

Late that day, mountain pioneers destroyed some isolated Yugoslav bunkers in the area penetrated by Kampfgruppe Palten. On that day, the governor of the Drava Banovina, Marko Natlačen met with representatives of the major Slovene political parties, and created the National Council of Slovenia, whose aim was to establish a Slovenia independent of Yugoslavia. When he heard the news of fifth column-led revolts within the 4th Army, Trifunović was alarmed, and proposed withdrawal from the border areas, but this was rejected by the commander of the 1st Army Group, Armijski đeneral Milorad Petrović. The front along the border with Italy was relatively quiet, with only patrol clashes occurring. The Yugoslav High Command ordered that the 7th Army capture Fiume, across the Rječina river from Sušak, but the order was soon rescinded. Over the next three days, LI Corps held the lead elements of its two divisions back while the rest of each division detrained in Graz and made their way to the border. All elements of both divisions had unloaded by 9 April. On the afternoon of 7 April, German Junkers Ju 87 Stuka dive bombers of Sturzkampfgeschwader 77 escorted by Messerschmitt Bf 109E fighters caught the Breguet 19s of the 6th Air Reconnaissance Group on the ground at Cerklje, destroying most of them. As a result of the revolts in the 4th Army, on the night of 7/8 April, Petrović ordered the 7th Army to begin to withdraw, first to a line through the Dravinja river, Zidani Most bridge and the right bank of the Krka river. This was subsequently moved back to the line of the Kupa river. On 8 April, disregarding orders from above, Palten led his Kampfgruppe south towards Maribor, and crossed the Pesnica river in pneumatic boats, leaving his unit vehicles behind. In the evening, Palten and his force entered Maribor unopposed, taking 100 prisoners. Kampfgruppe Palten was ordered to return to Spielfeld, and spent the rest of the invasion guarding the border. In the meantime, the forward elements of the two divisions consolidated their bridgeheads, with the 132nd Infantry Division securing Maribor, and the 183rd Infantry Division pushing past Murska Sobota.

The activities of Natlačen and his council continued from the day the invasion commenced, and the Yugoslav High Command soon ordered their arrest. However, the chief of staff of the headquarters of the 1st Army Group, Armiski General Leon Rupnik and the head of the operations staff, Pukovnik Franjo Nikolić did not carry out the orders. On 9 April, the 6th Air Reconnaissance Group airfield at Cerklje was again attacked by German aircraft.

During the night of 9/10 April, lead elements of the XLIX Mountain Corps, consisting of the 1st Mountain Division de-trained and crossed the border near Bleiburg and advanced southeast towards Celje, reaching a point about 19 km from the town by evening. Luftwaffe reconnaissance sorties revealed that the main body of the 7th Army was withdrawing towards Zagreb, leaving behind light forces to maintain contact with the German bridgeheads. When it received this information, 2nd Army headquarters ordered LI Corps to form motorised columns to pursue the 7th Army south, but extreme weather conditions and flooding of the Drava at Maribor on 10 April slowed the German pursuit.

On 10 April, as the situation was becoming increasingly desperate throughout the country, Dušan Simović, who was both the Prime Minister and Yugoslav Chief of the General Staff, broadcast the following message:

Fate
About 06:00 on 11 April, LI Corps renewed its push south towards Zagreb, with lead elements exiting the mountains northwest of the city in the evening of the same day, while the 1st Mountain Division captured Celje after some hard marching and difficult fighting. Emissaries from the newly-formed National Council of Slovenia approached the commander of XLIX Mountain Corps, General der Infanterie Ludwig Kübler to ask for a ceasefire. Also on 11 April, the Italian 2nd Army commenced offensive operations around 12:00, with the XI Corps pushing through Logatec towards Ljubljana, VI Corps advancing in the direction of Prezid, while strong formations attacked south through Fiume towards Kraljevica and towards Lokve. By this stage, the 7th Army was withdrawing, although some units took advantage of existing fortifications to resist.

To assist the Italian advance, the Luftwaffe attacked Yugoslav troops in the Ljubljana region, and the 14th Panzer Division, which had captured Zagreb on 10 April, drove west to encircle the withdrawing 7th Army. The Italians faced little resistance, and captured about 30,000 Yugoslav troops waiting to surrender near Delnice. On 12 April, the 14th Panzer Division linked up with the Italians at Vrbovsko, closing the ring around the remnants of the 7th Army, which promptly surrendered. The Croatian fascist organisation, the Ustaše, arrested the staffs of the 1st Army Group, and 4th and 7th Armies at Petrinja, and the 7th Army effectively ceased to exist as a formation. After a delay in locating appropriate signatories for the surrender document, the Yugoslav High Command unconditionally surrendered in Belgrade effective at 12:00 on 18 April.