Bolesław III Wrymouth (Bolesław III Krzywousty); 1085 – 1138) was Duke of Poland from 1102. He was the son of Duke Władysław I Herman and Judith of Bohemia, daughter of Vratislaus II of Bohemia. His wife, the mother of his children, was Salome von Berg-Schelklingen.
Boleslaw had his older stepbrother Zbigniew of Poland blinded, who died as a result.
In several gruesome attacks Boleslaw III ravaged Pomerania and murdered so many people, that for years later heaps of bones were left still unburied. In an attack during the winter of 1120-1121 he conquered Stettin, the capital city of the Pomeranians and is said to have put 18000 people to death, and to have additionally transported to Poland another 8000 people together with their wives and children. He took control of largely depopulated Pomerania (1119-1123), thus again gaining Polish access to the Baltic Sea for a short time. Boleslaw then tried to Christianize what was left of Pomerania's population after the massacre. He failed to find any willing Polish bishops, who all turned it down, and was able to convince a Spanish bishop, Bernard, wo was chased away.
Bernard retired to Bamberg where he saw to it that Otto of Bamberg would take up the mission to the Pomeranians. Otto succeeded in 1124. The local government of the Duke of Pomerania was left in place.
Bolesław also defeated troops of the Emperor Henry V, who came to the aid of Boleslaw's brother Zbigniew of Poland in (1109) at the Battles of Głogów and Psie Pole (the latter is known as the Battle of Hundsfeld). Boleslaw sought to keep his older brother from gaining the throne.
In the years 1113-1119 he had taken control over Pomerania.
Boleslaw ceased his tribute to the emperor upon his death in 1125.
In 1130 in alliance with the Danish prince Magnus I of Gothenland, Bolesław threatened Rügen. Polish forces delivered by Danish fleet compelled Ranis to recognize his rule over the island, but ultimately failed to accomplish that goal.
In 1135, Bolesław finally gave his belated oath of allegiance to the new Emperor Lothair II (Lothar von Supplinburg), and paid twelve years past due tribute. The emperor granted Boleslaw parts of Western Pomerania and Rügen as fiefs, however the emperor was not in control of these areas and Bolesław alsofailed to subdue them.
Before his death in 1138, Bolesław Wrymouth published his testament (Bolesław Wrymouth's testament) dividing his lands among four of his sons. The "senioral principle" established in the testament stated that at all times the eldest member of the dynasty was to have supreme power over the rest and was also to control an indivisible "senioral part": a vast strip of land running north-south down the middle of Poland, with Kraków its chief city. The Senior's prerogatives also included control over Pomerania, a fief of the Holy Roman Empire. The "senioral principle" was soon broken, leading to a period of nearly 200 years of Poland's feudal fragmentation.
Bolesław subsequently married Salome von Berg-Schelklingen, by whom he had 14 children (six sons and eight daughters), of whom six sons and five daughters are known: