Duchy of Racibórz
He was a son of Duke John I of Opava-Ratibor. John I had been the sole heir of the Duchy of Racibórz in 1365 and had founded the Opava-Ratibor branch of the family. When the Duchy of Opava was divided in 1377, John I had received the Duchies of Krnov and Bruntál. John II's mother was Anna, the daughter of Henry V of Głogów-Żagań.