Partition of Poland after the death of Bolesław III (1138)

Timeline

1. 1138Kraków · PolandBolesław III died in Kraków; his will stipulated that the kingdom was not to be inherited as a whole but divided among his sons by territory, and established the senioral principle whereby the eldest sat in Kraków as High Duke and ruled over his brothers. It was intended to prevent wars of succession but in fact marked the start of the fragmentation.
2. 1138–1139Greater Poland · Greater PolandWładysław II received Silesia and the senioral High Duchy, Bolesław IV received Masovia and Kuyavia, Mieszko III received Greater Poland, Henryk received Sandomierz, and Kazimierz received Wiślica; Poland's political map thus shattered into multiple hereditary duchies.
3. 1139–1140Silesia · SilesiaConflicts quickly arose among the sons over the senioral High Duchy and territorial borders; Władysław II and Mieszko III and others began courting German and Hungarian support. Poland entered a two-century period of feudal fragmentation in which central royal authority existed in name only.