The loss of Pomerania during the reign of
Casimir I the Restorer weakened the Polish state, and, during the second half of the 11th century, subsequent rulers were not able to recover all the lands that once belonged to
Mieszko I and
Bolesław I the Brave. Only after defeating Zbigniew and successfully opposing Bohemian claims against Silesia in 1109 was Bolesław III able to expand to the West.
Strengthening the Polish-Pomeranian borders The conquest of Pomerania had been a lifelong pursuit for Bolesław. His political goals were twofold: to strengthen the Polish border on the Noteć river line and to subjugate Pomerania. He intended to exercise Polish political overlordship but not actually incorporate Pomerania with the exception of
Gdańsk Pomerania and a southern belt north of the River
Noteć. By 1113, the northern border had been strengthened, including the fortification of
Santok,
Wieleń,
Nakło,
Czarnków,
Ujście and
Wyszogród. Some sources report that the border began at the mouth of the rivers Warta and Oder in the west, running along the
Noteć all the way to the
Vistula. Before Bolesław III began to expand in
Gdańsk Pomerania (Pomerelia), he normalized his political relations with Bohemia in 1114 at a great convention on the border of the
Nysa Kłodzka river.) with Vladislaus I and Otto II's sister-in-law, the German noblewoman
Salomea of Berg.
The conquest of Gdańsk Pomerania After normalising his relations with Bohemia, Bolesław conducted a successful expedition against Prussia in 1115. This secured Poland's north-east border, which allowed it to invade Gdańsk Pomerania. The conquest of this part of the Pomeranian lands from 1115 to 1119 achieved a long-time aim of previous Polish rulers: the complete incorporation of the territories on the Vistula River, including the castellany of Nakło, into Poland. The northern borders of the Polish duchy were probably established on the line of the rivers
Gwda and Uniesta (in later times these rivers were the boundary between Pomerania and the Oder Slavic). It is also possible that the border ran along the
Łeba. The local rulers of the conquered
Gdańsk and
Słupsk were replaced by Polish nobles. Bolesław also introduced a Polish clerical organisation in order to protect his interests in that territory. However, these areas refused to follow the church organization. The incorporation into the Polish Church occurred only during 1125–1126 at the time of the visit of the papal legate,
Gilles, Cardinal-Bishop of Tusculum.
Rebellion of Skarbimir During Bolesław's Pomeranian campaign, a rebellion led by Count Palatine
Skarbimir from the
Awdaniec family began. The rebellion was quelled by the duke in 1117 and the mutinous nobleman was blinded as punishment. The conflict between Bolesław and the Awdaniec family is difficult to explain due to the lack of sources. The cause was probably the growing influence of the family, Skarbimir's ambition, and his jealousy of Bolesław and his increased popularity. Other probable factors were the desire to establish Władysław II, Bolesław's first-born son, as the sole ruler after his death, or Boleslaw's fears of losing his position, as had happened in the conflict with Sieciech. Medieval historiography also associated the rebellion with the Law of Succession issued by Boleslaw. The underlying inheritance controversy arose between 1115 and 1116, after the birth of his second son, Leszek, first of his second marriage. According to one hypothesis, Skarbimir objected to the adoption of the statute, which changed the traditional Polish succession customs. In the suppression of the rebellion, a major role was played by
Piotr Włostowic of the
Labedz family, who replaced Skarbimir as Count Palatine. The rebellion of Skarbimir also underlined the importance of the conquest of Gdańsk Pomerania.
Intervention of Kievan Rus' The Rurikid ruler Vladimir II Monomakh and his sons are believed to have intervened in Skarbimir's rebellion. In 1118, Monomakh incorporated
Volhynia into his domains and expelled the ruler, Yaroslav Sviatopolkovich, then in Poland. In Yaroslav's place, Monomakh made his son Roman ruler of Volhynia, and after Roman's early death in 1119, replaced him with another son, Andrew, who invaded Polish territory in 1120 with the support of the
Kipchaks tribe. A year later, Bolesław, with his brother-in-law, the exiled Yaroslav, organised a retaliatory expedition to
Czermno. For several years thereafter, Bolesław intervened in the dynastic disputes of the
House of Rurik. who in 1122 captured Prince
Volodar. A year later, Bolesław intervened again in Volhynia, where he wished to restore Yaroslav. The expedition (aided by Bohemian, Hungarian, Peremyshl and Terebovl forces) failed due to the death of Yaroslav and the stubborn resistance of the besieged
Volodymyr-Volynskyi, aided by Skarbimir's supporters. This failed military expedition led to disturbances in the Polish-Hungarian-Halych alliance.
Conquest of Western Pomerania In 1121 (or 1119) Pomeranian Dukes
Wartislaw I and
Swietopelk I were defeated by Bolesław's army at the battle of
Niekładź near
Gryfice. Polish troops ravaged Pomerania, destroyed native cities, and forced thousands of Pomeranians to resettle deep into Polish territory. Bolesław's further expansion was directed to
Szczecin (1121–1122). He knew that this city was well defended by both the natural barrier of the Oder river and his well-built fortifications, like
Kołobrzeg. The only way to approach the walls was through the frozen waters of a nearby swamp. Taking advantage of the element of surprise, Bolesław launched his assault from precisely that direction and took control of the city. Much of the population was slaughtered and the survivors were forced to pay homage to the Polish ruler. Bolesław probably fought battles on the western side of the Oder, as well as near Lake Morzyce (now the German
Müritz), which were technically outside of Pomerania. At the same time,
Lothair, Duke of Saxony (and future Holy Roman Emperor), also moved against this area. According to contemporary sources, a Saxon army approached from above the
Elbe River in the direction of modern-day
Rostock. They conquered the
Warinis,
Circipanes,
Kessinians and part of the Tollensers tribes. This two-pronged expansion was probably the result of earlier unknown agreements between the rulers. This was the first step for the later Christianization of Pomeranian lands. In 1122, Bolesław finally conquered
Western Pomerania, which became a Polish fief. Duke Wartislaw I was forced to pay homage, as well as an annual
tribute of 500 marks of fine silver to the Polish ruler, and was further obliged to give military aid at Bolesław's request. In subsequent years, the tribute was reduced to 300 marks. This success enabled Bolesław to make further conquests. In 1123, his troops even reached
Rügen, but failed to conquer it.
Christianisation of Western Pomerania In order to strengthen ties with Pomerania, Bolesław organized a mission to Christianise the newly acquired territory. At the same time, he wished to subordinate Pomerania to the
Gniezno Archbishopric. Unfortunately, the first attempts made by unknown missionaries did not make the desired progress. Another attempt, officially sponsored by Bolesław and led by Bernard the Spaniard, who traveled to
Wolin during 1122–1123, ended in another failure. The next two missions were carried out in 1124–1125 and 1128 by Bishop
Otto of Bamberg (called the Apostle of Pomerania). After appropriate consultation with Bolesław, Bishop Otto set out on the first stage of Christianisation of the region in 1124. During the
mission Otto stayed first at Bolesław's court, where he was provided with appropriate equipment, fire and several clergymen for his trip to Pomerania. The Bishop was accompanied throughout his mission by the Pomeranian ruler Wartislaw I, who greeted him on the border of his domains, in the environs of the city of
Sanok. In
Stargard the pagan prince promised Otto his assistance in the Pomeranian cities as well as help during the journey. He also assigned 500 armored knights to act as guards for the bishop's protection, Primary missionary activities were directed to
Pyrzyce, In the first two towns, the Christianization went without resistance. In Kamień, the task was facilitated by the intercession of Wartislaw I's own wife and dignitaries. In 1127, the first pagan rebellions began to take place. These were due to both the large tribute imposed by Poland as well as a plague that descended on Pomerania, which was blamed on Christianity. Thanks to Otto's diplomacy, direct confrontation was avoided and in 1128, he embarked on another mission to Pomerania. Wartislaw I greeted Otto at
Demmin with some Polish knights. This time, more pressure was applied to the territories west of the Oder River, i.e.
Usedom,
Wolgast and
Gützkow, which weren't under Polish suzerainty. In retaliation for the sack of Płock by Wartislaw I in 1128, Polish-Danish troops took the Western Pomeranian islands of
Wolin and
Usedom. At the end of the 1120s, Bolesław began to implement an ecclesiastical organisation of Pomerania.
Gdańsk Pomerania was added to the
Diocese of Włocławek, known at the time as the Kujavian Diocese. A strip of borderland north of Noteć was split between the
Diocese of Gniezno and
Diocese of Poznan. The bulk of Pomerania was, however, made an independent
Pomeranian bishopric (whose first bishop,
Adalbert, was one of the participants in the missionary expedition and a former Polish royal chaplain), set up in the territory of the
Duchy of Pomerania in 1140, and, after Bolesław died in 1138, the duchy became independent of Poland. Despite this setback, Norbert continued to attempt to subdue the Polish Church during 1132–33. A call was made in the
Curia on behalf of the Polish bishops. The Polish bishops didn't appear before
Pope Innocent II, which resulted in the issuing of the
Bull Sacrosancta Romana in 1133, which confirmed the sovereignty of the Archbishopric of Magdeburg over the Polish Church and the projected Pomeranian dioceses. The formal
privilegium maius was the culmination of Norbert's efforts. Bolesław, trying to save his past efforts in Pomeranian politics, submitted at Merseburg in 1135.
Conquest of Rügen and alliance with Wartislaw I To consolidate his power over Pomerania, Bolesław conducted an expedition to the island of
Rügen in 1130 with Danish support. The fleet transported Polish troops to Rügen, but the intended battle on the island never happened, because, at the sight of the Polish-Danish combined forces, the defending
Rani recognized Bolesław's overlordship. After the successful invasion of the Danish capital,
Roskilde, in 1134, Bolesław formed an alliance with Wartislaw I of Pomerania against King
Eric II of Denmark, an ally of Emperor Lothair III. The role of the Polish duke was limited to aiding the
House of Griffins, not due to a real interest in Danish affairs. The Danish, after repelling the first attack, led a successful retaliatory expedition and expansion into Pomerania. == Congress of Merseburg ==