Waldemar I, Prince of Anhalt-Zerbst
Waldemar I, Prince of Anhalt- Zerbst( died 7 January 1368) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Zerbst.
He was the youngest son of Albert I, Prince of Anhalt- Zerbst, by his second wife Agnes, daughter of Conrad, Margrave of Brandenburg- Stendal.
Albert II, Prince of Anhalt-Zerbst
Albert II, Prince of Anhalt- Zerbst( died 17 July 1362) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Zerbst.
He was the third son of Albert I, Prince of Anhalt- Zerbst, but the eldest child born to his second wife Agnes, daughter of Conrad, Margrave of Brandenburg- Stendal.
Waldemar III, Prince of Anhalt-Zerbst
Waldemar III, Prince of Anhalt- Zerbst( died 1391) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Zerbst.
He was the youngest son of John II, Prince of Anhalt- Zerbst, by his wife Elisabeth, daughter of John I, Count of Henneberg- Schleusingen.
Rudolph, Prince of Anhalt-Zerbst
Rudolph of Anhalt-Zerbst (Harzgerode, 28 October 1576 – Zerbst, 30 July 1621), was a German prince of the House of Ascania and ruler of the unified Principality of Anhalt.
From 1603, he was ruler of the principality of Anhalt-Zerbst.
Rudolph was the fifth son of Joachim Ernest, Prince of Anhalt, but third-born son by his second wife Eleonore, daughter of Christoph, Duke of Württemberg.
John Louis I, Prince of Anhalt-Dornburg
John Louis I, Prince of Anhalt- Dornburg( 4 May 1656, in Zerbst – 1 November 1704, in Dornburg), was a German prince of the House of Ascania and ruler of the principality of Anhalt- Dornburg.
He was the sixth( but fourth surviving) son of John VI, Prince of Anhalt- Zerbst, by his wife Sophie Auguste, daughter of Frederick III, Duke of Schleswig- Holstein- Gottorp.
Karl I, Prince of Anhalt-Zerbst
Karl I of Anhalt- Zerbst( 17 November 1534 in Dessau – 4 May 1561 in Zerbst), was a German prince of the House of Ascania and ruler of the principality of Anhalt- Zerbst.
He was the eldest son of John V, Prince of Anhalt- Zerbst, by his wife Margaret, daughter of Joachim I Nestor, Elector of Brandenburg.
Bernhard VII, Prince of Anhalt-Zerbst
Bernhard VII of Anhalt- Zerbst( 17 March 1540 – 1 March 1570), was a German prince of the House of Ascania and ruler of the principality of Anhalt- Zerbst.
He was born and died in Dessau, and was the third and youngest son of John V, Prince of Anhalt- Zerbst by his wife Margaret, daughter of Joachim I Nestor, Elector of Brandenburg.
Anthony Günther, Prince of Anhalt-Zerbst
Anthony Günther, Prince of Anhalt- Zerbst( 11 November 1653 – 10 December 1714) was a German prince of the House of Ascania.
He was born in Zerbst, the fourth( but second surviving) son of John VI, Prince of Anhalt- Zerbst, by his wife Sophie Auguste, daughter of Frederick III, Duke of Schleswig- Holstein- Gottorp.
John VI, Prince of Anhalt-Zerbst
John VI of Anhalt-Zerbst (Zerbst, 24 March 1621 – Zerbst, 4 July 1667), was a German prince of the House of Ascania and ruler of the principality of Anhalt-Zerbst.
He was the only son of Rudolph, Prince of Anhalt-Zerbst, by his second wife Magdalene, daughter of John VII, Count of Oldenburg.
Charles, Prince of Anhalt-Zerbst
Charles William, Prince of Anhalt- Zerbst( German: Karl Wilhelm; 16 October 1652, in Zerbst – 3 November 1718, in Zerbst), was a German prince of the House of Ascania and ruler of the principality of Anhalt- Zerbst.
He was the third( but eldest surviving) son of John VI, Prince of Anhalt- Zerbst, and Sophie Auguste, daughter of Frederick III, Duke of Schleswig- Holstein- Gottorp.
His two older brothers died before his birth.

Question: Who is the paternal grandfather of John Vi, Prince Of Anhalt-Zerbst?
Answer: Joachim Ernest, Prince of Anhalt