This was a German operation against the partisan forces of Josip Broz Tito in the northern part of German-occupied Yugoslavia (21 October/12 November 1943).
Following the armistice which Italy reached with the Allies in September 1943, all of the occupying Italian forces in the Slovene coastal region, Istrian peninsula, Croat coastal region, Gorski Kotar, Notranjsko and Dolenjsko were disarmed even as partisan forces started to arrive with the object of establishing a large new area of liberated Yugoslavia, and also of creating several new brigades as well as the 18th, 30th and 31st ‘Slovenia’ Divisions of the partisan army. The immediate effect of this change so far as the Germans were concerned was the severance or, at best, severe disruption of their lines of communication between Italy and the valley of the Sava river.
On 19 September German high command ordered Generalfeldmarschall Erwin Rommel, currently heading Heeresgruppe ‘B’ in northern Italy, to suppress the communist uprising and destroy the partisan forces in Gorski Kotar, eastern Slovenia, the Istrian peninsula, and the Slovenian and Croat littorals, so securing the eastern coast of the Adriatic Sea in that area. Rommel allocated the task to SS-Obergruppenführer und General der Waffen-SS Paul Hausser’s II SS Panzerkorps, and this formation’s operation was the first stage of a series of offensives known to the partisans as the 'Sixth Enemy Offensive'.
The offensive was undertaken, with only limited success, in four phases before the undertaking was terminated to allow the movement of German forces to Italy.
The Axis order of battle for the first and second phases of the operation, which took place on 21/25 October and 26/30 October, totalled 50,000 men as well as more than 150 tanks, 25 assault guns and 90 self-propelled anti-tank guns of the 191st Grenadierregiment, 194th Grenadierregiment and 211th Grenadierregiment and 171st Artillerieregiment of Generalleutnant Wilhelm Raapke’s 71st Division reinforced by the 138th Reserve-Gebirgsjägerregiment and 1st Panzerregiment of SS-Obergruppenführer und General der Waffen-SS Josef Dietrich’s 1st SS Panzerdivision ‘Leibstandarte SS Adolf Hitler’, 901st Panzergrenadierregiment, two battalions of the 19th SS Polizeiregiment, SS Bataillon ‘Karstjäger’, 1/1st Panzerregiment of Generalmajor Walter Krüger’s 1st Panzerdivision, 1st Gebirgsjägerbataillon, 21st Panzergrenadierregiment of Generalleutnant Maximilian Freiherr von Edelsheim’s 24th Panzerdivision, and 132nd Regiment of Generalleutnant Heinrich Deboi’s 44th Division ‘Hoch- und Deutschmeister’.
For the third phase of the operation, starting on 31 October, the German order of battle was based on the 194th Grenadierregiment of the 71st Division reinforced by the 901st Panzergrenadierregiment, the 14th SS Polizeiregiment, the 44th Division ‘Hoch- und Deutschmeister’, the 32nd Grenadierregiment and the 44th Aufklärungsabteilung.
For the fourth and last phase of the operation, lasting to 12 November, the German order of battle, comprising 50,000 men, more than 110 tanks, 10 assault guns and more than 140 self-propelled anti-tank guns, was headed by the II SS Panzerkorps and the German-Slovene Domobran garrison in Ljubljana, and included the 1st SS Panzerregiment of the 1st SS Panzerdivision, 44th Division, 132nd Grenadierregiment, 44th Aufklärungsabteilung, 303rd Infanterieregiment (turkestanisch) and 314th Infanterieregiment (turkestanisch) and 236th Artillerieregiment (turkestanisch) of Generalleutnant Hermann Franke’s 162nd Division (turkestanisch), Wehrmannschaftbataillon ‘Süd’, Gebirgsjägerregiment ‘Admont’, Gebirgsjägerbataillon ‘Heine’, 14th SS Polizeiregiment, reinforced 19th SS Polizeiregiment, 901st Panzergrenadierregiment, 112th Artillerieregiment, small units of SS-Obergruppenführer und General der Waffen-SS Herbert Gille’s 5th SS Panzerdivision ‘Wiking’, small units of SS-Obergruppenführer und General der Waffen-SS Fritz Stolz Edler von Barancze’s 11th SS Panzergrenadierdivision ‘Nordland’, 194th Grenadierregiment and other elements of the 71st Division, and one Slovene home defence battalion.