Kakko and Tasso, along with their brothers Radoald and Grimoald, escaped the Avars and evaded capture, successfully setting themselves up as Gisulf's successors. During their reign, they ruled over the Slavs of the valley of the Gail up to Matrei and imposed a tribute upon them.
In the aftermath of their narrow escape from the Avars, Kakko and Tasso, along with their brothers Radoald and Grimoald, successfully asserted their authority as successors to Gisulf's throne. During their reign, they exerted control over the Slavs in the Gail valley, collecting a form of tribute.