John V could keep his external opponent, Edzard I, Count of East Frisia in check through alliances. During the Saxon feud, he and the united Dukes of Brunswick-Lüneburg attacked Edzard in January 1514. He was then able to conquer Butjadingen and Stadland and parts of the Frisian Wehde. He tried to keep the Stadland area with Esenshamm and Abbehausen as allodial property. However, in 1517, he had to accept them as fiefs from Henry V, Duke of Brunswick-Lüneburg. Initially, the dukes of Brunswick occupied Butjadingen. However, after a failed peasants uprising in 1515, they gradually transferred ownership to John V, and by 1523, Butjadingen was definitely owned by Oldenburg.