Mieszko I Tanglefoot in 1163, and thanks to the intervention of the Emperor Frederick Barbarossa, Mieszko and his older brother Bolesław I the Tall returned to Silesia. Mieszko and Bolesław I the Tall co-ruled the Duchy of Wrocław during the period 1163–1173. At first, their rule did not extend over the major Silesian cities, which remained under the control of Bolesław IV the Curly, the current High Duke of Poland. The brothers retook them in the year 1165, taking advantage of Bolesław IV's involvement in a crusade against the Prussians. However, soon Mieszko began his efforts to obtain his own Duchy, maybe in
Mieszko I of Poland expanding and improving the so-called war monarchy system. According to existing sources, Mieszko I was a wise politician, a talented military leader, and a charismatic ruler. He successfully used diplomacy, concluding alliances, first with Bohemia, then Sweden, and the Holy Roman Empire. In foreign policy, he placed the interests of his country foremost, even entering into agreements with his former enemies. On his death, he left to his sons a country with greatly expanded territories, and a well-established position in Europe. Mieszko I also enigmatically appeared as "Dagome" in a papal document dating to about 1085, called "Dagome iudex", which