Butvydas or Pukuveras (also known as Боудивидъ, Liutauras, Пукувер (Pukuvier) Pukuwer or Pucuwerus; died 1295) was Grand Duke of Lithuania from c. 1290 to 1295.^[1][2] His influence was strong during his brother Butigeidis's reign.^[1] This led some historians to believe, that they were co-rulers, much like the grandsons Algirdas and Kęstutis. During his short reign, Butvydas tried to defend the duchy against the Teutonic Knights; he also attacked Masovia, an ally of the knights. He was a direct ancestor of the Gediminids.