1138 AD – Kazimierz Sprawiedliwy was born. Polish ruler.
– Also known as Casimir the Just.
1177 AD – He became the duke of Kraków and of Sandomierz.
– He drove his brother Mieszko III from power at Cracow and became the principal duke of Poland.
1180 AD – At the Congress of Leczyca, the nobility and clergy, in return for privileges he had granted them, vested Casimir’s descendants with hereditary rights to the crown.
– Casimir himself was never crowned king.
1194 AD – Died on May 5th.