Duke Wartislaw VIII died on 20 August 1415. He was buried in the St. Peter's Church in Wolgast. After his death, his widow Agnes and regency council acted as regent for his own sons Barnim VIII and Swantibor IV as well as his brother's sons Wartislaw IX and Barnim VII, until Wartislaw IX, the eldest of the four, took over in 1417.
