The Duchy of Bytom (Polish: Księstwo Bytomskie) or Duchy of Beuthen (German: Herzogtum Beuthen) was one of many Silesian duchies. It was established in Upper Silesia about 1281 during the division of the Duchy of Opole and Racibórz among the sons of Duke Władysław Opolski. The duchy's capital was Bytom (Beuthen), formerly part of Lesser Poland until in 1177 the Polish High Duke Casimir II the Just had attached it to the Silesian Duchy of Racibórz.
When Władysław's second son Casimir became Duke of Bytom, he at first ruled jointly with his brother Duke Bolko I of Opole and from 1284 on alone. The conflict with his Piast cousin Duke Henryk IV Probus of Silesia-Wrocław led Casimir to seek shelter from King Wenceslaus II of Bohemia and in 1289 he became the first Silesian Piast duke to submit himself under Bohemian overlordship.
With the death of Casimir's grandson Duke Bolesław in 1355 the Bytom branch of the Piasts became extinct and in the following inheritance dispute his widow Margareta of Sternberg had to cede the northern part of the duchy including the lordship of Koźle to Duke Konrad I of Oleśnica, while the remaining part was bequested to Duke Casimir I of Cieszyn. Bytom remained divided until in 1459 Duke Wenceslaus I of Cieszyn sold his portion to Duke Konrad IX the Black of Oleśnica and the duchy was reunited under his rule.
Bytom [ˈbɨtɔm] (German: Beuthen) is a city in Silesia in southern Poland, near Katowice. The central-western district of the Upper Silesian Metropolitan Union – metropolis with the population of 2 million. Bytom is located in the Silesian Highlands, on the Bytomka river (tributary of the Kłodnica).
The city has belonged to the Silesian Voivodeship since its formation in 1999. Previously it was in Katowice Voivodeship. Bytom is one of the cities within the conurbation of the Katowice urban area (total population approximately 2.7 million) as well as within a greater Silesian metropolitan area populated by about 5,294,000 people. The population of the city is 183,251 (June 2009).
Bytom is located on the range "Bytom-Katowice", in the Upland of Miechowice, which is in turn a central part of the Silesian Upland. The city straddles between north latitudes 50°19′ i 50°26′ and east longitudes 18°47′ i 18°58′. It reaches 346 m (1,135 ft) at the highest point, in wildlife reserve of Segiet, plunging to the lowest point 249 m (817 ft) above sea level, in a valley of river Bytomka, giving an average altitude of 280 to 290 m (919 to 951 ft) above sea level. The city itself is not placed exclusively in the Upland of Miechowice, where only central part of the town stands. The rest of the city reaches as far as valleys of Drama and Szarlejka to the north, Brynica to the north and east and the river Bytomka to the south.