what are its origins?
Various theories have claimed that Gediminas was either his predecessor Grand Duke Vytenis' son, his brother, his cousin, or his hostler.
Family of Gediminas
Various theories have claimed that Gediminas was either his predecessor Grand Duke Vytenis' son, his brother, his cousin, or his hostler. 
what is family of gediminas? A group of family members of Gediminas, Grand Duke of Lithuania.
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Family of Gediminas [SEP] Origins
Because written sources of the era are scarce, Gediminas' ancestry, early life, and assumption of the title of Grand Duke in ca. 1316 are obscure and continue to be the subject of scholarly debate. Various theories have claimed that Gediminas was either his predecessor Grand Duke Vytenis' son, his brother, his cousin, or his hostler. For several centuries only two versions of his origins circulated. Chronicles—written long after Gediminas' death by the Teutonic Knights, a long-standing enemy of Lithuania—claimed that Gediminas was a hostler to Vytenis; according to these chronicles, Gediminas killed his master and assumed the throne. Another version introduced in the Lithuanian Chronicles, which also appeared long after Gediminas' death, proclaimed that Gediminas was Vytenis' son.