'Dubrovnik I' was a Croat and German operation against the 32nd Division of the newly formed X 'Zagreb' Corps of the partisan forces led by Marshal Josip Broz Tito in the region behind Hrvatsko and round Kalnik in Axis-occupied Yugoslavia (21 January/6 February 1944).
The operation was undertaken primarily by Croat forces (1st Poglavnik Bodyguard Regiment and Ustase Pukovnik Rafael Boban’s 5th Ustase Active Service Brigade), reinforced by German units and a German battery of medium howitzers, under the command of an Ustase officer, Ustase Pukovnik Ante Moskov. The object of the undertaking was to re-establish land communication between Varazdin and Zagreb by recapturing Novi Marof and Varazdinske Toplice, and at the same time to establish strongholds in the Bednja valley for offensive operations against partisan-held territory in Kalnik and Podravina, and to prevent the movement of the 14th 'Slovenia' Division. This last was moving to Styria, which it reached on 6 February without a major battle through its entire movement through Croatia.
The Croat operation was carried out successfully, although the partisan forces escaped into the mountains and thus managed to avoid major engagements except on 1 February near Varazdinske Toplice, where the 1/1st Poglavnik Bodyguard Regiment engaged two battalions of the 2nd 'Matija Gubec' Brigade of the 32nd Division. The Ustase lost 11 men killed and 15 wounded, while the partisans reported 27 dead, seven wounded and 46 missing. The operation was continued on 7 February as 'Dubrovnik II'.