Traidenis died soon afterwards, and assistance to Semigalians, exhausted by constant warfare, diminished. Traidenis is the first known Lithuanian duke to have died a natural death. All others before him were assassinated or killed in battle. Family Brothers Bardis, Liesis, and Svalkenis were Eastern Orthodox and died in fights with Halych-Volhynia Sirputis assisted his brother in military campaigns Daughter Gaudemunda, married Bolesław II, Duke of Masovia, becoming Duchess of Masovia References Further reading 1220 births 1282 deaths Grand Dukes of Lithuania