This battle's losing side was later besieged at Marienburg before accepting the Peace of Thorn in 1411. For 10 points each:
[10m] Name this battle, which is commemorated by the King Jagiełło Monument in Central Park. This 1410 battle was a decisive victory for Poland and Lithuania against the Teutonic Knights.
ANSWER: Battle of Grunwald [or Battle of Žalgiris; or First Battle of Tannenberg; prompt on Battle of Tannenberg]
[10h] The Polish-Lithuanian-Teutonic War was partly prompted by the territorial dispute over Samogitia, which this ruler refused to cede. This ruler previously signed the Treaty of Ostrów to end a conflict with his cousin Jogaila.
ANSWER: Vytautas the Great [or Vytautas Didysis]
[10e] Previously, Vytautas tried to improve relations with the Teutonic Knights by crusading against this khanate. Vytautas was defeated at the Battle of the Vorskla River by this khanate, legendarily named either for their wealth or the color of their tents.
ANSWER: Golden Horde [or Ulug Ulus; or Kipchak Khanate; or Ulus of Jochi]
<Alexandra Hardwick , History - European - Eastern European>