Dynastic ambitions were shattered when the pro-Frankish faction was able to seize power under Obelerio degli Antoneri in 804. Obelerio brought Venice into the orbit of the Carolingian Empire. However, by calling in Charlemagne's son Pepin, rex Langobardorum, to his defence, Obelerio raised the ire of the populace against himself and his family and they were forced to flee during Pepin's siege of Venice. The siege proved a costly Carolingian failure. It lasted six months, with Pepin's army ravaged by the diseases of the local swamps and eventually forced to withdraw. A few months later Pepin himself died, apparently as a result of a disease contracted there.