Tags: Noble.
John III of Holstein-Plön (ca. 1297–1359) called John the Mild was a Count of Schauenburg and Holstein-Plön and Holstein-Kiel ruling Holstein-Plön (1312–1316 and again 1350–1359) and Holstein-Kiel (1316–1359). Together with Count Gerhard III of Holstein-Rendsburg John III was the lord ruling in guardianship the Danish Duchy of Schleswig 1332–1340.