Wikipedia
Seneslau, also Seneslav or Stănislau, was a Vlach voivode mentioned in a diploma issued by king Béla IV of Hungary (1235–1270) on 2 July 1247; the diploma granted territories to the Knights Hospitaller in the Banate of Severin and Cumania. According to the diploma, the king gave the territories east of the Olt River to the knights, with the exception of the territory of voivode Seneslau.
The name of Seneslav is of Slavic origin. Seneslau held central and southern Muntenia (i.e., the territories along the rivers Argeş and Dâmboviţa). The Romanian historian Ioan Aurel Pop suggests that Seneslau was quasi independent of the king of Hungary. According to the Hungarian historian István Vásáry, his title (voivode) suggests that he had a territorial unit under his jurisdiction.
The diploma of Béla IV also refers to the kenazates of John, Farcaş and voivode Litovoi. Although the names of Seneslau and Litovoi are of Slavic origin, they are expressly said to be Vlachs (Olati) in the king's diploma.