John I, Count of Oldenburg Count of Oldenburg (1204–1270) Parents Agnes von Berg-Altena Christian II, Count of Oldenburg Children Moritz of Oldenburg-Delmenhorst Otto II of Oldenburg-Delmenhorst Hedwig of Oldenburg and Delmenhorst Heinrich von Oldenburg-Delmenhorst Christian III, Count of Oldenburg Siblings Otto of Oldenburg Partners Richza von Hoya