On July 13, 1617, Duke Adam Vjenceslav of Tešina, a member of the Polish Pjastović dynasty, was born. This dynasty ruled Poland from 930 to 1370 and gave birth to a number of Polish kings, and later remained in power in Silesia and Mazovia. After the extinction in Mazovia in 1526, the Pjastovićs continued to rule only in Silesia, divided into a number of branches. One of these branches ruled the aforementioned Silesian duchy of Tešín (German: Teschen, Polish: Cieszyn, Czech: Těšín) and it was this that lasted the longest. Duke Adam Vjenceslav of Tešin was the penultimate male duke of Tešin from the Pjastović dynasty, and with his son and daughter that dynasty became completely extinct.
The Duchy of Teszyn was in an interesting position, close to today’s border of Poland, the Czech Republic and Slovakia. The city of Tešín, meanwhile, is literally divided into two parts by the state border between Poland and the Czech Republic – the Czech part is called Český Těšín, and the Polish part Cieszyn. If we take into account that Slovakia once belonged to the Kingdom of Hungary, it can be concluded that the Duchy of Teszyn was located on the border of Hungary, Poland and the Czech Republic. Furthermore, the neighboring Silesian duchy of Tešín was the duchy of Oświęcim (Auschwitz), which was even formed by separation from Tešín.
In the time of Adam Wenceslaus of Teszyn (late 16th and early 17th century), his duchy was located at the crossroads of the Holy Roman Empire, the Kingdom of Poland and the Kingdom of Hungary. Adam Vjenceslav was initially a Protestant, but later converted to Catholicism. A good portion of the nobility and the rest of the population in his duchy also converted to Catholicism over time. The duke died on this day in 1617, at the age of only 42 years.