He was active as ruler of Lombardy and worked to expand the Frankish empire. In 791, he marched a Lombard army into the Drava valley and ravaged Pannonia, while his father marched along the Danube into Avar territory. Charlemagne left the campaigning to deal with a Saxon revolt in 792. Pepin and Duke Eric of Friuli continued, however, to assault the Avars' ring-shaped strongholds. The great Ring of the Avars, their capital fortress, was taken twice. The booty was sent to Charlemagne in Aachen and redistributed to all his followers and even to foreign rulers, including King Offa of Mercia. A celebratory poem, "De Pippini regis Victoria Avarica", was composed after Pepin forced the Avar khagan to submit in 796. This poem was composed at Verona, Pepin's capital after 799 and the centre of Carolingian Renaissance literature in Italy. The "Versus de Verona" (c. 800), an urban encomium of the city, likewise praises king Pepin. The "Historia Langobardorum codicis Gothani" hails Pepin's campaign against Benevento and his liberation of Corsica "from the oppression of the Moors."