Boleslaw II, as the eldest son of Casimir, had in 1058 inherited Greater and Lesser Poland as well as the Mazovian, Pomeranian, and Silesian lands.

His younger brothers Wladyslaw Herman and Mieszko had become governors of the remaining provinces.

However Mieszko dies relatively early, in 1065, at which point his lands come under the authority of Boleslaw II.

His father had left him a stable country; Boleslaw II continues his foreign policy of surrounding his realm with allied kingdoms in order to prevail against the extensive Holy Roman Empire in the west; he aims to have Poland eventually bordering only allied countries.