Casimir II, Duke of Cieszyn
Casimir II of Cieszyn  (– 13 December 1528) was a Duke of Cieszyn since 1477, ruler over Koźle during 1479–1509, since 1493 ruler over Wołów, over Pszczyna during 1498–1517, from 1506 over Opava, Duke of Głogów since 1506 (for life).
Also he was Landeshauptmann General of Silesia during 1497–1504 and 1507–1517, since 1517 until his death, Landeshauptmann over the Upper Silesia.
He was the eldest child and only son of Bolesław II, Duke of Cieszyn, by his wife Anna, daughter of Ivan Vladimirovich, Prince of Bielsk.
Frederick of Cieszyn
Frederick of Cieszyn( b. 1480/83- d. June 1507), was a Polish prince member of the House of Piast in the Cieszyn branch.
He was the eldest son of Casimir II, Duke of Cieszyn, by his wife Johanna, daughter of Wiktoryn of Poděbrady, Duke of Opawa.
Wenceslaus II, Duke of Cieszyn
Wenceslaus II of Cieszyn
(b. 1488/96 - d. 17 November 1524), was a Duke of Cieszyn since 1518 until his death (as co-ruler of his father).
He was the second son of Casimir II, Duke of Cieszyn, by his wife Johanna, daughter of Wiktoryn of Poděbrady, Duke of Opawa.
Margaret of Bohemia, Duchess of Wroclaw
Margaret of Bohemia( 21 February 1296 – 8 April 1322) was a daughter of Wenceslaus II of Bohemia and his first wife, Judith of Habsburg.
Hedwig of Cieszyn
Hedwig of Cieszyn( 1469 – 6 April 1521) was a Polish princess.
She was the only child of Przemysław II, Duke of Cieszyn by his wife Anna, daughter of Duke Bolesław IV of Warsaw.
Elizabeth Lucretia, Duchess of Cieszyn
Elizabeth Lucretia of Cieszyn; 1 June 1599 – 19 May 1653), was a reigning Duchess of Cieszyn( Teschen, Těšín) from 1625 until her death.
Born as the third child and second daughter of Adam Wenceslaus, Duke of Cieszyn( by his wife Elisabeth, daughter of Gotthard Kettler, Duke of Courland), she was the last ruler of Cieszyn from the Polish Piast dynasty.
Adam Wenceslaus, Duke of Cieszyn
Adam Wenceslaus of Cieszyn( 12 December 1574 – 13 July 1617), was a Duke of Cieszyn from 1579 until his death.
He was the second but only surviving son of Wenceslaus III Adam, Duke of Cieszyn, by his second wife Sidonia Katharina, daughter of Francis I, Duke of Saxe- Lauenburg.
His older half- brother, Frederick Casimir, only son of Wenceslaus III Adam's first marriage, died a few years before he was born, in 1571.
Wenceslaus II of Legnica
Wenceslaus II, Duke of Legnica( 1348 – 30 December 1419) was a Duke of Legnica from 1364( only nominal; from 1409 he reigned alone and personally) until 1413, Bishop of Lebus( 1375 – 82) and Breslau( Wroclaw)( 1382 – 1417; also Duke of Nysa-Otmuchów.
He was the second son of Wenceslaus I of Legnica, by his wife Anna, daughter of Casimir I, Duke of Cieszyn.
Casimir I, Duke of Cieszyn
Casimir I of Cieszyn( 1280/90 –), was Duke of Cieszyn from 1315, Duke of Siewierz from 1337 and Duke of Bytom from 1357.
He was the second son of Mieszko I, Duke of Cieszyn by his wife, probably called Grzymisława.
Wenceslaus III Adam, Duke of Cieszyn
Wenceslaus III Adam of Cieszyn (December 1524 – 4 November 1579) was a Duke of Cieszyn from 1528 until his death.
He was the second but only surviving son of Wenceslaus II, co-Duke of Cieszyn, by his wife Anna, daughter of Frederick I, Margrave of Brandenburg-Ansbach.
He was born one month after his father's death, on 17 November 1524.

Question: Who is Wenceslaus Ii, Duke Of Cieszyn's paternal grandfather?
Answer: Bolesław II, Duke of Cieszyn