Piasts' reign is coming to end on Casimir the Great, who have no sons. Polish throne comes to Anjous. Thanks to the marriage of Saint Jadwiga of Poland with Lithuanian Grand Duke Jogaila, an alliance is made and a new dynasty - Jagiellons, who rule Poland for next two hundred years
The action of the season covers the years 1376-1399. After the death of King Casimir, fights for the Polish throne begin. He is succeeded by his nephew, King Louis, who also has no son. His youngest daughter Hedwig becomes the ruler of Poland. Polish nobles force her to marry Jogaila, Grand Duke of Lithuania. The Polish-Lithuanian union is established.