Sleenzane

Silesians (Polish: Ślężanie) were a tribe of West Slavs, specifically of the Lechitic/Polish group, inhabiting territories of Lower Silesia, near Ślęża mountain and Ślęza river, on the both banks of the Oder, up to the area of modern city of Wrocław. They were the first permanent inhabitants of the site of Wrocław where they build a fort on Ostrów Tumski in the 9th century or earlier, which at the time was an island on the Oder.

Their tribal name was derived from the name of the mountain and the river, which most likely came from the old Polish word Ślagwa, meaning "humid", which refers to the climate of the area. The name of the region in turn, Silesia, comes from their language and tribal name. Along with the Opolans, the Ślężanie comprised one of the two major tribes in Silesia. They bordered the Dziadoszanie to their north. The Biezunczanie's territory lay to the west. Other, more minor, Silesian tribes of the time included the Golensizi, Trzebowianie (who might have actually been part of the Ślężanie), Bobrzanie (who were probably subjects of the Dziadoszanie) and the Głubczyce, further to the south.

The Bavarian Geographer, which refers to them as the Sleenzane, states that they had 15 settlements, or gords (civitates), and lists them as one of several tribes located in Silesia. The Prague charter (description of borders of the Prague bishopric) from 1086 refers to them with the alternative name of Zlasane. Thietmar's Chronicle, from the second decade of the 11th century, calls them the Silensi. Their tribal name was known to the Franks and the Byzantines.

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