text: This dynasty's power was weakened after a member issued a Testament creating the Seniorate Province as part of a plan to split his kingdom between his four heirs, and his widow Salomea of Berg.
full_question: This dynasty's power was weakened after a member issued a Testament creating the Seniorate Province as part of a plan to split his kingdom between his four heirs, and his widow Salomea of Berg. One branch of this house, which included rulers known as "Tanglefoot" and "the Exile," was surrendered after this dynasty's final ruler signed the Treaty of Trentschin renouncing its claim to Silesia. Earlier, when this dynasty's ruler Henry II the Pious was killed at the Battle of Legnica, its Silesian branch was left exposed. Its final ruler succeeded a king known as the "Elbow-High" for his short stature, and extended protection to Jewish citizens. This dynasty's second king lent his army to the Kievan Rus' ruler Sviatopolk to battle Yaroslav the Wise, and inherited this dynasty from Mieszko I. For 10 points, name this dynasty which included Casimir the Great and Boleslaw the Brave, the first ruling house of Poland, which should not be confused with the Premyslids.
first_sentence: This dynasty's power was weakened after a member issued a Testament creating the Seniorate Province as part of a plan to split his kingdom between his four heirs, and his widow Salomea of Berg.
raw_answer: Piast dynasty