According to Russian chronicles, Prince Fyodor acted as an emissary during negotiations with Batu Khan.
During these negotiations, Batu Khan demanded that he be given he be given Fyodor's wife to marry.
[1] Prince Fyodor adamantly refused, and Batu Khan had him killed.
[2][1] As told by Russian chroniclers and poets, Eupraxia subsequently committed suicide rather than to surrender to captivity of Batu Khan during the Mongol invasion of Russia.
[2][3] The author of The Tale of the Destruction of Ryazan bewails the martyrdom of Eupraxia.