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In page Anne of Bohemia, Duchess of Silesia:

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Around the age of twelve (in 1216) she was married to the Piast prince Henry II the Pious, member of the Silesian branch of the Piast dynasty, the son and heir of Duke Henry the Bearded.[1] During internal political struggles, the Silesian Piasts gained large parts of the Polish territories upon the assassination of High Duke Leszek the White in 1227. Henry the Bearded inherited the Duchy of Greater Poland in 1231, and in the following year attained the Seniorate Province and the Polish throne at Kraków. After his death on 19 March 1238 he was succeeded by his son Henry II, co-ruler in the Silesian lands since 1226.