This was a German, Italian and Croat operation, otherwise known as 'Trio II', against the partisan forces of Josip Broz Tito in the puppet state of Croatia in Axis-occupied Yugoslavia (5/12 May 1942).
The undertaking’s objective was the pinning and destruction of partisan and Četnik forces (1st and 2nd Proletarian Brigades, 18 partisan detachments and two independent partisan battalions totalling about 18,000 men) in eastern Bosnia after they had been driven into the Foča area by ‘Trio’.
The German contribution to the operation was Generalleutnant Johann Fortner’s 718th Division and the 3/737th Regiment of Generalmajor Paul Hoffmann’s 717th Division, that of the Italians part of Generale di Divisione Giovanni Maccario’s 1st Divisione alpina ‘Taurinense’, elements of Generale di Divisione Lazzaro Maurizio de Castiglione’s 5th Divisione alpina ‘Pusteria’, elements of Generale di Brigata Vittorio Ruggero’s 22nd Divisione ‘Cacciatori delle Alpi’, 1st Gruppo alpino ‘Valle’, 2nd Gruppo di carri veloci ‘San Marco’, 12th Gruppo d’artigliera and several sections of armoured cars, and that of the Croats the Zagreb Cavalry, 9th Artillery Group, and 2nd, 3rd and 4th Military Frontier Battalions.
By the end of April, a strengthening of the Italian forces in this part of Croatia and it was possible to mount a substantial effort against the partisans, who had withdrawn into the Italian zone, and were concentrated around Tito’s headquarters at Foča. The German and Croat units began pushing to the south from the area of Goražade on 5 May, supported by artillery and air attacks, while the Italian divisions fought their way toward Foča from the east, west and south. On 9 May, Tito’s forward positions were overrun and the next day the combined Axis forces prepared to assault the town. Tito ordered his 3,500 or so battered partisans to evacuate, taking their estimated 600 wounded with them, and move to the north-west into western Bosnia. These forces broke through the encirclement between the two Italian mountain divisions on 12 May and made good their escape.
Axis commanders in occupied Yugoslavia thought ‘Foča’ relatively successful, costing the partisans a claimed 168 killed and 1,309 captured, for only light German, Italian and Croat casualties.