Two battalions (440 soldiers) of 1st Regiment of Polish Legions in World War I (part of Austro-Hungarian Army) clashed with the Imperial Russian Army, in an attempt to stop a Russian offensive.

On November 17, 4th and 6th Battalions, supported by field artillery, took positions on the hill of Holy Cross, located between Krzywoploty and Bydlin.

The battle, which lasted for two days, was a success for the Legions, as they managed to halt a local Russian offensive.

Jozef Pilsudski called the battle “our Thermopylae”, and following his initiative, a monument in the shape of a stone cross was unveiled at the Bydlin Cemetery in 1920.

To commemorate the battle, soldiers of the Legions founded in 1937 a school in Bydlin.