Lengvenis was born to Algirdas and his second wife
Uliana of Tver. In 1387, Lengvenis commanded one of Lithuanian formations in a battle with the
Teutonic Order. Invited by the Novgorodians themselves, Lengvenis was first regent in
Great Novgorod in 1389–1392, responsible to Jogaila, the Grand Duke of Lithuania. He was baptized in the Eastern Orthodox rite as Semën and received the title of Prince of Great Novgorod. After Lengvenis lost this title in 1392,
Vytautas the Great appointed him in 1393 as the
Prince of Mstislavl in then eastern
Lithuania. In 1406–1411, Lengvenis, once again, was regent of Great Novgorod, this time responsible to Vytautas. As ruler of Novgorod he led battles against
Pskov Republic,
Livonian Order, and
Sweden. In 1410, Lengvenis participated in the
Battle of Grunwald. He led his own "
banner", and a certain Georgy- the next banner in the famous list of chronicler
Jan Długosz. Often this George is considered the son of Lengvenis, Yury. Many historians believe that under the command of Lengvenis there were three banners of
Smolensk land, which played a significant role in the battle. In 1411 Lengvenis participated in the signing of the
Peace of Thorn. He was married to
Maria Dmitrovna, princess of
Moscow, the daughter of
Dmitry Donskoy. In 1380, he founded the Monastery of the Dormition in Pustynki near Mstsislaw in then eastern Lithuania, now
Belarus. ==See also==