| Aigusta Anastasia of Lithuania | |
| Succession: | Princess consort of Moscow |
| Reign: | 1341 – 11 March 1345 |
| Death Date: | 11 March 1345 |
| Burial Place: | Moscow Kremlin |
| Consort: | yes |
| Spouse: | Simeon of Moscow |
| Issue: | Vasily Konstantin Vasilisa |
| Full Name: | Anastasia Gediminova Russian: Анастасия Гедиминовна |
| House: | Gediminids |
| Father: | Gediminas of Lithuania |
Aigusta Anastasia of Lithuania (Russian: Анастасия Гедиминовна|Anastasiya Gediminovna; – 1345) was the princess of Moscow during her marriage to Simeon, the grand prince of Vladimir and prince of Moscow.[1] Most likely she was the daughter of Gediminas, the grand duke of Lithuania.[1]
There is no direct evidence that she was a daughter of Gediminas, but because of her high-profile marriage, most historians have concluded that she was a member of Gediminas' family.[2] She was born probably between 1316 and 1321.[3]
Aigusta was baptized as Anastasia in order to marry Simeon of Moscow in November or December 1333.[3] The marriage had great potential because Lithuania and Moscow were fierce rivals for supremacy in Ruthenia, but conflicts broke out again in 1335, just two years after the marriage.[4]
Her two sons Vasily and Konstantin did not survive infancy; her daughter Vasilisa in 1350 married Mikhail Vasilevich of Kashin, a Tverite prince opposing Lithuania.[5] Her brother Jaunutis sought her help when he was deposed by Algirdas in 1345. Immediately before her death on March 11, 1345, Augusta became a nun. She was buried within the Moscow Kremlin at a monastic church whose construction she had sponsored.[5]