At the beginning of his reign, he warred against the Saracens and then made a treaty with them after they appeared beneath his walls in 929. He then allied with Lombards Atenulf III of Benevento, with whom he signed a pact, and Landulf I, joint-prince of Benevento, against the Byzantines. A Greek force was sent to Apulia and the rebellious vassals were constrained to recognise the authority of the emperor in Constantinople. John then confirmed a treaty with the princes salve fidelitate sanctorum imperatorum.
