Gediminas' origins are unclear, but recent research suggests that Skalmantas, an otherwise unknown historical figure, was Gediminas' grandfather or father and could be considered the dynasty's founder. Because none of his brothers or sisters had known heirs, Gediminas, who sired at least twelve children, had the advantage in establishing sovereignty over his siblings. Known for his diplomatic skills, Gediminas arranged his children's marriages to suit the goals of his foreign policy: his sons consolidated Lithuanian power within the Grand Duchy of Lithuania, while his daughters established or strengthened alliances with the rulers of areas in modern-day Russia, Ukraine and Poland.