Marie Friederike of Hesse-Kassel
Marie Frederike of Hesse-Kassel (14 September 1768, Hanau – 17 April 1839, Hanau) was a German noblewoman and by marriage Princess and later Duchess of Anhalt-Bernburg.
She was a daughter of William I, Elector of Hesse, and his wife, Princess Wilhelmina Caroline of Denmark.
Bernhard V, Prince of Anhalt-Bernburg
Bernhard V, Prince of Anhalt- Bernburg( died 24 June 1420) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Bernburg.
He was the eldest son of Henry IV, Prince of Anhalt- Bernburg, by his wife Sophie, a possible member of the House of Stolberg.
John I, Prince of Anhalt-Bernburg
John I, Prince of Anhalt- Bernburg( died 5 June 1291) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Bernburg.
He was the eldest son of Bernhard I, Prince of Anhalt- Bernburg, by his wife Princess Sophie, daughter of King Abel of Denmark.
Bernhard VI, Prince of Anhalt-Bernburg
Bernhard VI, Prince of Anhalt- Bernburg( died 2 February 1468) was a German prince of the House of Ascania and ruler of the Principality of Anhalt- Bernburg.
He was the eldest son of Otto III, Prince of Anhalt- Bernburg, by his first unknown wife.
Louise of Anhalt-Dessau (1709–1732)
Louise, Princess of Anhalt- Bernburg( née Princess Louise of Anhalt- Dessau; 21 August 1709 – 29 July 1732) was the first wife and consort of Victor Frederick, Prince of Anhalt- Bernburg.
Prince Alexander of Prussia
Prince Friedrich Wilhelm Ludwig" Alexander" of Prussia( 21 June 1820 – 4 January 1896) was the eldest child of Prince Frederick of Prussia and his wife, Princess Luise of Anhalt- Bernburg.
Henry IV, Prince of Anhalt-Bernburg
Henry IV, Prince of Anhalt- Bernburg( died 7 July 1374) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Bernburg.
He was the second son of Bernhard III, Prince of Anhalt- Bernburg, by his first wife Agnes, daughter of Rudolf I, Duke of Saxe- Wittenberg.
Otto IV, Prince of Anhalt-Bernburg
Otto IV, Prince of Anhalt- Bernburg( died 1 May 1415) was a German prince of the House of Ascania and ruler of the principality of Anhalt- Bernburg.
He was the youngest son of Otto III, Prince of Anhalt- Bernburg, by his unknown first wife.
Princess Luise of Anhalt-Bernburg
Princess Luise of Anhalt-Bernburg (30 October 1799, Ballenstedt – 9 December 1882, Eller, Düsseldorf) was a German Princess.
As the daughter of Alexius Frederick Christian, Duke of Anhalt-Bernburg and his wife Marie Friederike of Hesse-Kassel, she was a Princess of Anhalt-Bernburg and member of the House of Ascania.
By her 21 November 1817 marriage to Prince Frederick of Prussia she was a princess of Prussia.
She had two children: Prince Alexander of Prussia (21 June 1820, Berlin – 4 January 1896, Berlin) and Prince George of Prussia (12 February 1826, Düsseldorf – 2 May 1902, Berlin).
Alexius Frederick Christian, Duke of Anhalt-Bernburg
Alexius Frederick Christian of Anhalt- Bernburg( 12 June 1767 – 24 March 1834), was a German prince of the House of Ascania.
From 1796 until 1807 he was Reigning prince of the principality of Anhalt- Bernburg, and from 1807 until 1834 the first Duke of the Duchy of Anhalt- Bernburg.

Question: Who is Princess Luise Of Anhalt-Bernburg's maternal grandfather?
Answer: William I, Elector of Hesse