The Peace of
A letter by Sven Ekdahl is evidence that one side in this battle employed a tactical retreat borrowed from the Golden Horde, though Stephen Turnbull argues that they messed it up by returning late to the field. Prior to this battle, the winning side united its forces at Czerwinsk and committed alleged atrocities at Gilgenburg. Before this battle, one commander sent a pair of swords to the other side as an insult. The Peace of (*) Thorn showed the failure of the winning side to capitalize on this victory. This battle's namesake swords became an emblem of the winning side after being offered to Vytautas and Jogaila by the losing side's Grand Master, Ulrich von Jungingen. For ten points, name this 1410 defeat of the Teutonic Knights by the newly formed Kingdom of Poland-Lithuania.
A letter by Sven Ekdahl is evidence that one side in this battle employed a tactical retreat borrowed from the Golden Horde, though Stephen Turnbull argues that they messed it up by returning late to the field.
Battle of Grunwald [or First Battle of Tannenberg; or 1410 Battle of Tannenberg; do not accept "Second Battle of Tannenberg" or "1914 Battle of Tannenberg"]