He was a ruling count of Dießen and Andechs in the Duchy of Bavaria, of Plassenburg and Kulmbach in Franconia, as well as bailiff of Benediktbeuern Abbey.

According to the Europäische Stammtafeln genealogy, he was probably the elder son and heir of Count Arnold of Dießen (d. 1098) and his wife Gisela of Schweinfurt, a daughter of Duke Otto III of Swabia.

When his daughter Kunigunde entered Admont Abbey, he donated 15 Hufen (oxgangs) of land in Moosburg, Carinthia to the monastery.

She was of royal blood: her paternal grandmother was Sophia, a daughter of King Béla I of Hungary, from the House of Árpád.

Together, they had the following children: After Sophia's death, he married Kunigunde,[1] a daughter of Count Egbert II of Formbach-Pitten, the heiress of Formbach.