As part of her marriage negotiations, she insisted on remaining a member of the Eastern Orthodox Church, despite her future husband's allegiance to Calvinism.

[2] He was a son of Vladimir, the prince of Kiev, and grandson of Algirdas, the grand duke of Lithuania.

In the mid-1450s, Goštautas planned to depose Grand Duke Casimir IV Jagiellon and to install his son-in-law Simeon Olelkovich.

His descendants continued to claim the rights to the region, but the voivodeship was ruled by appointed officials (voivodes) from other noble families.

Disappointed by prevailing politics, Mikhailo Olelkovich organized opposition to Casimir IV and even attempted a coup in 1481.

[6] In 1471, Mikhailo had also been involved in a brief alliance when Novgorod Republic invited him to become its ruler in a bid to break away from Moscow's influence.