Bytom ziemowit (also German: Siemowit / Semowit von Beuthen und Gleiwitz; (pl) Siemowit bytomski; (cs) Zemovít Bytomsko-Koselský) (1292 - after July 1, 1342), was the duke of the duchy Bytom in Upper -Silezia in 1312-1316 and duke of the duchy of Gliwice from 1340 until his death. He was the third son of Duke Casimir of Bytom and Helena Halicka.
Ziemovit obtained the Duchy title over the two-tier Duchy Bytom while his father was still alive, and was first declared a duke in 1311. After the death of these in 1312 he retained these possessions, and the same was true of his older brother Bolesław, who remained the duke of Toszek and Wladislaus who received the scepter of Duchy Koźle, and his younger brother Mieszko who admitted to clergy but besides also became Duke of Siewierz. Presumably there was some disagreement between the brothers about the distribution of the estate; It is clear that from 1316 Wladislaus conducted the Duchy title over Bythom, and it is not known if Ziemovit was still co-ruling. Wladislaus did not leave Ziemovit completely empty: after the death of one of the neighbors Leszek from Ratibor, the area Gliwice that was penned to him was back to Bythom, and Ziemowits became the Duke. In the sources, Ziemowits is appointed for the first time in 1342. Later life signs are not available; It is not known or where he died, or where he would be buried.
Since Ziemowits did not have a progeny, Gliwice's part-ownership became once again included in the Duchy of Bythom after his death. Literature Sources
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