Question: Petras Jonaitis Mantigirdaitis, was a prominent noble of the Grand Duchy of Lithuania. in 494, Mantigirdaitis was sent on the diplomatic mission to negotiate peace with the Grand Duchy of Moscow and marriage of Helena of Moscow to where?
Sentence (from "Helena of Moscow"): Her childless marriage to Grand Duke of Lithuania and later King of Poland Alexander Jagiellon was a constant source of tension between the Grand Duchy of Moscow and the Grand Duchy of Lithuania.
Relevant evidence: Yes