On 13 September 1195, a fratricidal clash over the succession to the throne of Krakow took place on the Mozgawa River. It was the largest and bloodiest battle related to the division of districts in Poland during this period.
by Rafał Gumiński
Medieval warfare primarily involved rapid raids into enemy territory and prolonged sieges. In the 12th century, this mode of combat was prevalent in Western Europe, where numerous castles and strongholds dotted the landscape. Large-scale, open-field clashes were relatively rare due to their high risk and the need for precise coordination. Instead, minor conflicts and skirmishes were more common.
However, civil wars and internal conflicts over the throne were different. These situations often led to more frequent, intense, and bloody battles, as contenders sought to gain an advantage quickly and decisively, even if it was risky.
The Disintegration of the State
On October 28, 1138, Bolesław III Wrymouth, the ruler of Poland, died. His death activated the succession law he had created, commonly known as “Wrymouth’s testament,” which was based on the principle of seniority. According to this law, the state was divided into districts, each ruled by one of the deceased ruler’s sons, with supreme power vested in the eldest son. Only the most senior had the authority to determine the direction of the state’s foreign policy. Bolesław III intended to prevent power disputes among his sons after his death, as similar conflicts had occurred in the past not only in Poland but also in Ruthenia and Bohemia. A power struggle took place after the death of Mieszko I, Casimir the Restorer, and Boleslaw Wrymouth’s father, Władysław Herman. So the prince had real reasons to expect such a situation after his demise. “Wrymouth’s testament” was intended to be a compromise that would ensure each son’s authority while maintaining the superior authority’s continuity.
The eldest son, Władysław II the Exile, became the senior ruler in the senior district, a strip of land connecting all districts, stretching through Krakow, Kalisz, Gniezno, and Gdańsk. In addition, he received control over lands in Silesia and Lubuska. Mazowsze was given to Bolesław IV the Curly, Greater Poland to Mieszko III the Old, and Henryk Sandomierski (born after his father’s death) was given the land of Sandomierz.
The Fight for the Krakow Throne
Unfortunately, the order of the seigniorage had already been disturbed in the first generation of princes. Shortly after taking power, Prince Senior Władysław II the Exile began to enter into conflicts with his younger brothers, also known as the junior princes. The final split occurred when he seized the land granted to Salomea, the widow of Bolesław III Wrymouth. This action led to a declaration of war by his brothers against the senior prince. As a result, Władysław II fled the country in 1146 and sought support at the court of the German Emperor Konrad III. However, the imperial expedition to defend Władysław II ended in a fiasco.
After Konrad III’s death, the imperial throne was taken over by Frederick I, who, after being persuaded by the Exile, decided to intervene again in 1157. Although Frederick I’s expedition was successful, instead of restoring Władysław to the throne, he accepted the fief homage of the fugitive’s younger brother, Bolesław the Curly, who assumed the role of senior prince.
Władysław passed away in 1159 at Altenburg Castle in Thuringia. After his death, his two sons were able to return to Poland. They assumed power in his hereditary district, which was Silesia.
The Rule of Mieszko III the Old
After the death of Bolesław the Curly, another son of Bolesław Wrymouth, Mieszko III the Old, became the senior ruler. He proclaimed himself the prince of all Poland (in Latin: dux totius Poloniae). Mieszko’s rule was characterized by an attempt to strengthen the country’s central authority and minimize the magnates’ influence. As a symbol of this effort, he placed the royal title on coins minted by Jewish minters. However, the duke pursued a ruthless fiscal policy, which led to frequent corruption of the coinage. Additionally, Mieszko successfully conducted a large-scale dynastic policy, resulting in Poland regaining sovereignty over Western Pomerania.
However, Mieszko’s harsh reign led to a rebellion from the nobles in 1177, including his younger brother Casimir II the Just and son Odon. After futile attempts at gaining Czech and imperial support, the Pomeranians helped Mieszko regain power in Greater Poland in 1181. Mieszko did not give up his efforts to win the throne of Krakow, which had ended up in the hands of Casimir the Just.
The Battle of Mozgawa
His initial attempts brought only temporary success. However, the death of Casimir the Just on May 5, 1194, reawakened Mieszko’s hopes of gaining supremacy. The magnates of Lesser Poland, remembering the duke’s firm and strict rule, preferred to see Casimir’s sons Leszek and Konrad, supported by their mother Helena Znojemska and Mikołaj Gryfita, the voivode of Kraków, on the throne. The dispute eventually led to a battle fought on September 13, 1195, on the Mozgawa River in today’s Świętokrzyskie Province.
The eight-year-old Leszek the White, chosen as the senior prince, was supported by troops from Lesser Poland and Mazovia under the command of Mikołaj Gryfita, with reinforcements from Roman Halicki, the prince of Włodzimierz. Mieszko III the Old commanded troops from Greater Poland and Kuyavia and was supported by the Silesian princes – Mieszko I Tanglefoot and Jarosław of Opole. While the chronicle of Jan Długosz mentions the participation of the Pomeranian prince Mszczuj I, this is not true.
The clash is described in the Kronika Wielkopolska and the chronicle of Wincenty Kadłubek. The battle took place in two stages. In the first part, Mieszko III’s Silesian reinforcements had not yet arrived at the battlefield. Yet Mieszko III the Old achieved victory over the armies of the Ruthenians and Lesser Poland. Roman Halicki suffered an injury, and Mieszko was wounded, while his son Bolesław died in battle.
The loss of leadership broke the fighting spirit of the Kuyavian-Greater Poland troops, which began to retreat. However, Leszek the White’s army also withdrew due to significant losses. As a result, the battle remained unresolved.
The second stage commenced with the arrival of Silesian reinforcements led by Mieszko Tanglefoot and Jarosław of Opole. They encountered late troops on the side of Leszek the White, commanded by Gowork, the ruler of Sandomierz, who decided to attack the legion of the Silesian princes. The Silesian army triumphed in this clash, and Goworek was taken prisoner. Despite the victory in the second phase, the outcome was inconclusive, and the throne of Kraków remained in the hands of Leszek and his mother, Helena.
Negotiations of the Defeated
The battle did not discourage Mieszko III. Instead, he recognized that his goal would not be achieved through armed struggle. Consequently, he started talks with Helena, whose position in relation to the nobles of Lesser Poland was uncertain. In 1198, in exchange for Kuyavia, Mieszko III the Old regained the title of prince superior and power in Kraków, which he retained until his death on March 13 or 14, 1202, with a small break in 1199.
The Battle of Mozgawa also had broader implications. The Lwów historian Stanisław Smolka noted that “together with the corpses of the fallen in the Battle of Mozgawa, the principle of the monarchical supremacy of the capital of Krakow was buried,” thus recognizing this battle as the symbolic end of the so-called second Piast monarchy and the beginning of the disintegration of the Polish state.
Author: Rafał Gumiński
Translation: Alicja Rose & Jessica Sirotin
