History of Poland during the Piast dynasty of Lesser Poland, the country of the Vistulans, and of Silesia (both taken by Mieszko from the Czech state during the later part of the 10th century), Mieszko's state reached its mature form, including the main regions regarded as ethnically Polish. The Piast lands totaled about in area, with an approximate population of under one million. Initially a pagan, Mieszko I was the first ruler of the Polans tribal union known from contemporary written sources. A detailed account of aspects of Mieszko's early reign was given by Ibrâhîm ibn Ya`qûb, a Jewish traveler, according to whom Mieszko was one of
Mieszko I Tanglefoot the Sandomierz nobles captured in the battle). On 22 March 1201 Jarosław of Opole died. The Duchy of Opole was then inherited by his father Bolesław the Tall, with whom the late Duke was recently reconciled. Bolesław the Tall died only nine months later, on 7/8 December 1201, leaving all his lands to his eldest (and only) surviving son Henry I the Bearded. Mieszko was determined to obtain Opole and made a surprise attack at the beginning of 1202. The Duke managed to obtain Opole, which was from then on definitely joined to his lands. Despite this victory, Mieszko wanted