Mieszko III (c. 1122/25 – 13 March 1202), sometimes called Mieszko the Old, was Duke of Greater Poland from 1138 and High Duke of Poland, with interruptions, from 1173 until his death.
He was the fourth and second surviving son of Duke Bolesław III Wrymouth of Poland, by his second wife Salomea, daughter of the German count Henry of Berg-Schelklingen.
The Duchy of Poznań (Polish: Księstwo poznańskie; Latin: Ducatus Posnaniensis) was a feudal district duchy in Greater Poland, with its territorial and administrative core in the Poznań Land — the region surrounding the city of Poznań. Its capital was Poznań. The duchy was established in 1177, following the partition of the Duchy of Greater Poland after a rebellion against Mieszko III. Duke Odon of the Piast dynasty became its first ruler.
Initially, Poznań remained a fiefdom within the broader Duchy of Poland — a term commonly applied to the fragmented realm, which some sources continue to refer to as the Kingdom of Poland — until 1227, when Poznań gained independence as a duchy. It existed in this form until 1279, when it was united with the duchies of Gniezno and Kalisz under the rule of Przemysł II, forming a reconstituted Duchy of Greater Poland.
Casimir II the Just (Polish: Kazimierz II Sprawiedliwy; 28 October 1138 – 5 May 1194) was Duke of Wiślica in Lesser Poland from 1166 to 1173, and Duke of Sandomierz from 1173 onward. In 1177, he became ruler of the Polish Seniorate Province at Kraków and thereby High Duke of Poland — a position he held until his death, though briefly interrupted by his elder brother and predecessor, Mieszko III.
In 1186, Casimir inherited the Duchy of Masovia from his nephew Leszek, becoming the progenitor of the Masovian branch of the royal Piast dynasty and great-grandfather of the later Polish king Władysław I the Elbow-high. The honorific title "the Just" was not contemporary and first appeared in the 16th century.
The Duchy of Kalisz was a feudal district duchy in Greater Poland, with its territorial and administrative core in the Kalisz Land — the region surrounding the city of Kalisz. Its capital was Kalisz. The duchy was established in 1177, following the partition of the Duchy of Greater Poland after a rebellion against Mieszko III. Duke Casimir II the Just of the Piast dynasty became its first ruler.
Initially, Kalisz remained a fiefdom within the broader Duchy of Poland — a term commonly applied to the fragmented realm, which some sources continue to refer to as the Kingdom of Poland — until 1227, when Kalisz gained independence as a duchy. It existed in this form until 1279, when it was united with the duchies of Gniezno and Poznań under the rule of Przemysł II, forming a reconstituted Duchy of Greater Poland.
The Duchy of Gniezno was a feudal district duchy in Greater Poland, with its territorial and administrative core in the Gniezno Land — the region surrounding the city of Gniezno. Its capital was Gniezno. The duchy was established in 1177, following the partition of the Duchy of Greater Poland after a rebellion against Mieszko III. Duke Casimir II the Just of the Piast dynasty became its first ruler.
Initially, Gniezno remained a fiefdom within the broader Duchy of Poland — a term commonly applied to the fragmented realm, which some sources continue to refer to as the Kingdom of Poland — until 1227, when Gniezno gained independence as a duchy. It existed in this form until 1279, when it was united with the duchies of Kalisz and Poznań under the rule of Przemysł II, forming a reconstituted Duchy of Greater Poland.