It is worth to mention that even though most of Sypniewski clan (the ancestors of Feliks Sypniewski) and their estates were located within State of the Teutonic Order at that time, they have supported Polish-Lithuanian King Jagiello and took active part in this battle against Teutonic Order.
In January 1402, instead of traveling to the wedding of Jogaila and Anna of Cilli, Švitrigaila, disguised as a merchant, traveled to Marienburg, the capital of the Teutonic Knights.
They formulated the Treaty of Dubysa, by which Jogaila promised to accept Christianity, become an ally of the Order, and give the Order some territory of Samogitia up to the Dubysa River.
•
A major stand-off between the two armies ended without a battle in the Treaty of Ugra, by which Velikiy Novgorod was granted to Jogaila's brother Simeon Lingwen, and the important city of Pskov to Jogaila's envoy Jerzy Nos, the latter settlement a clear violation of the treaty of Raciąż.