Within the adjacent Silesian Beskids to the east, the Vistula River rises and turns eastwards, the Biała and Przemsza tributaries mark the eastern border with Lesser Poland.

According to the 9th century Bavarian Geographer, the West Slavic Opolanie tribe had settled on the upper Oder River since the days of the Migration Period, centered on the gord of Opole.

Upon its dissolution after 906, the region fell under the influence of the Přemyslid rulers of Bohemia, Duke Spytihněv I (894–915) and his brother Vratislaus I (915–921), possibly the founder and name giver of the Silesian capital Wrocław (Czech: Vratislav).

Finally, in 1137, the Polish prince Bolesław III Wrymouth (1107–1138) came to terms with Duke Soběslav I of Bohemia, when a peace was made confirming the border along the Sudetes.

However, this arrangement fell apart when upon the death of Bolesław III and his testament the fragmentation of Poland began, which decisively enfeebled its central authority.

In the early 13th century the ties of the Silesian Piasts with the neighbouring Holy Roman Empire grew stronger as several dukes married scions of German nobility.

Promoted by the Lower Silesian Duke Henry I the Bearded, from 1230 also regent over Upper Silesia for the minor sons of his late cousin Duke Casimir I of Opole, large parts of the Silesian lands were settled with German immigrants in the course of the Ostsiedlung, establishing numerous cities according to German town law.

The plans to re-unify Silesia shattered upon the first Mongol invasion of Poland and the death of Duke Henry II the Pious at the 1241 Battle of Legnica.

Upper Silesia further fragmented upon the death of Duke Władysław Opolski in 1281 into the duchies of Bytom, Opole, Racibórz and Cieszyn.

Upper Silesia was hit by the Hussite Wars and in 1469 was conquered by King Matthias Corvinus of Hungary, while the Duchies of Oświęcim and Zator fell back to the Polish Crown as a part of Lesser Poland.

After the 1620 Battle of White Mountain, the Catholic Emperors of the Habsburg dynasty forcibly re-introduced Catholicism, led by the Jesuits.

The earliest exact census figures on ethnolinguistic or national structure (Nationalverschiedenheit) of the Prussian part of Upper Silesia, come from year 1819.

show that large demographic changes took place between 1819 and 1910, with the region's total population quadrupling, the percent of German-speakers increasing significantly, and that of Polish-speakers declining considerably.

[2] Polish authors before 1918 estimated the number of Poles in Prussian Upper Silesia as slightly higher than according to official German censuses.

In early 1919, the Polish–Czechoslovak War broke out around Cieszyn Silesia, whereafter Czechoslovakia gained the Trans-Olza strip in addition to the Hlučín Region.

The plan to divide the region was suggested by the Inter-Allied Commission on Upper Silesia, headed by the French general Henri Le Rond.

[13] (Niederschlesiens Ostmark[17]) During the German invasion of Poland, which started World War II in September 1939, German troops committed numerous massacres of Polish civilians in the region, including at Gostyń, Łaziska Górne, Jankowice, Zgoń, Lędziny, Świętochłowice, Katowice, Pasternik, Pszczyna, Siemianowice Śląskie and Wyry.

The majority of the German-speaking population that had not fled was expelled, an activity that was euphemized as "transfers [to] be effected in an orderly and humane manner" in accordance with the decision of the victorious Allied powers at their 1945 meeting at Potsdam.

And later, in the years 1945-1989, a large number of Poles from various parts of Poland settled in Upper Silesia, who received work, e.g. in the mines.

In the second half of the twentieth century, dishes from the Polish borderland cuisine (potato pancakes, dumplings with cheese, red borscht, bigos) gained popularity in Upper Silesia.

Football, ice hockey and volleyball teams from Upper Silesia enjoyed great success either historically or recently.