Treniota was Grand Duke of Lithuania from 1263 to 1264.
Depiction of Treniota from chronicles of Alexander Guagnini, published in 1578
Mindaugas was the first known Grand Duke of Lithuania and the only crowned King of Lithuania. Little is known of his origins, early life, or rise to power; he is mentioned in a 1219 treaty as an elder
Treniota
…spelled Troniata; Belarusian: Транята, romanized: Traniata; c. 1210 – 1264) was Grand Duke of Lithuania from 1263 to 1264. Treniota was the nephew of Mindaugas, the first and only king of Lithuania. While Mindaugas had converted to Christianity in order to discourage Livonian Order and Teutonic Knights attacks…
Mindaugas, as depicted in the chronicles of Alexander Guagnini (1611)
Baptism of Mindaugas, 17th century portrait
Šeimyniškėliai Hillfort, possibly the site of Voruta Castle, alleged capital of Mindaugas
The Papal bull issued by Pope Innocent IV establishing Lithuania's placement under the jurisdiction of the Bishop of Rome, and discussing Mindaugas's baptism and coronation