His family acquired the fortress of Tusculum from Ptolemy II somehow before December 1152, when he sold his rights over Tusculum to Pope Eugene III. In 1155, he acted on behalf of Adrian IV in negotiations with Frederick Barbarossa. In 1156, he was at Benevento to accept the submission of William I of Sicily to the pope. This submission resulted in the confirmation of the Treaty of Benevento. After the papal election of 7 September 1159, Oddone wrote to Louis VII of France exhorting him to support Alexander III. When Alexander was arrested by supporters of the imperialist Antipope Victor IV, it was Oddone who freed him and sent to safety in Campania.
Oddone took over the military leadership of the city of Rome during the absence of Alexander and even afterwards. His son Leo was captured in battle with the emperor's troops in 1167 and he himself led the largest army of Roman citizens since the days of the Roman Empire into battle at Monte Porzio, where he was defeated by Christian I, Archbishop of Mainz.