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, Duke of Cieszyn The Obituary of the Church of St. Vincent in Wrocław showed the existence of a certain "Grzymisława, Duchess of Opole" ("Grimizlaua ducissa Opuliensis") who was buried there around 13 September 1286. Her parentage is also unknown, but her name suggests a Russian origin, probably member of the Rurikids. Her title suggests that she may have been the wife of Mieszko I or the first wife of Bolko I (Mieszko I's brother), or maybe a completely different person. Also, the exact date of their marriage was uncertain, but after a further reconstructions of their children's birth dates, was placed between 1275