Sigismund Kęstutaitis
After the death of Vytautas and during the Lithuanian Civil War (1431–1435), Rumbaudas was taken captive by the Poles, but was released. He first supported Sigismund Kęstutaitis. After the coup against Švitrigaila in August 1432, Sigismund even appointed Jaunius, brother of Rumbaudas, as Voivode of Vilnius. However, already at the end of 1432, Rumbaudas participated in a failed plot against Sigismund. For that he and Jaunius were executed.