Battle of Ostrołęka (1831)
The Battle of Ostrołęka of 26 May 1831 was one of the largest engagements of Poland's November Uprising. Throughout the day, Polish forces under Jan Skrzynecki fought for the control over the town of Ostrołęka against the assaulting Russian forces of Hans Karl von Diebitsch. Although by the end of the day the town was still in Polish hands and the two sides suffered comparable losses, the battle is usually considered a Polish defeat because of the Russian army's almost unlimited strategic reinforcement capability. The Polish Army could not similarly replenish its casualties.