She was the only daughter of Duke Kazimierz III of Gniewkowo[1] and his wife, whose name and origins are unknown; her brother, Władysław the White, was later a candidate for the Polish throne.
[citation needed] By 1323, King Charles I of Hungary wanted to increase influence over Stephen II, Ban of Bosnia.
[2] Some[citation needed] believe that Catherine of Bosnia, Countess of Cilli, was daughter of Elizabeth of Kuyavia and Stephen II, while others argue that Catherine was daughter of Stephen II's brother Vladislaus and his wife Jelena Šubić.
Elizabeth may have also had a son, Vuk who may have survived infancy but he did not outlive his father so never became Ban of Bosnia.
[citation needed] Banness Elizabeth was buried in Bobovac in a tomb which she shared with her husband, brother-in-law Vladislaus and sister-in-law Jelena.