Mestwin II was a Duke of Gdańsk Pomerania, member of the Samborides dynasty. He ruled Gdańsk Pomerania as a sole ruler from 1273 to 1294.
Monument of Mestwin II at Adam Mickiewicz Park in Oliwa.
The Gąsawa massacre was an attack on the night of 23-24 November 1227, during a council of Polish Piast dukes that was being held near the village of Gąsawa in Kuyavia, Poland. The High Duke of Poland
The Gąsawa Congress, by Matejko. Participants in discussion before the massacre.
Monument at the site of Leszek's death
Death of Leszek the White, by Matejko. Leszek, High Duke of Poland, was caught in his bath but fled on horseback. The attackers caught up with him a few kilometers out of Gąsawa.