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?
Petras Jonaitis Mantigirdaitis:  Then Mantigirdaitis presented Alexander with a naked sword and a reminder that Alexander was elected to be a just ruler. Helena of Moscow: Helena Ivanovna of Moscow (Russian: Елена Ивановна ; Lithuanian: "Elena" ; Polish: "Helena Moskiewska" ; 19 May 1476 – 20 January 1513) was daughter of Ivan III the Great, Grand Prince of Moscow, and an uncrowned Grand Duchess of Lithuania and Queen of Poland as she would not convert from Eastern Orthodoxy to Catholicism. Helena of Moscow:  Instead of guaranteeing peace, Helena's marriage gave her father Ivan III an excuse to interfere in Lithuanian affairs accusing Alexander of mistreating Helena and repressing Orthodox believers.
i don't know