Prince Bernhard of Saxe-Weimar-Eisenach (1878–1900)
Prince Bernhard of Saxe-Weimar-Eisenach ("Bernhard Carl Alexander Hermann Heinrich Wilhelm Oscar Friedrich Franz Peter"; 18 April 1878 – 1 October 1900) was a member of the Grand Ducal House of Saxe-Weimar-Eisenach and a Lieutenant in the Prussian Army.
He bore the titles "Prince of Saxe-Weimar-Eisenach, Duke of Saxony" with the style "Highness".
Princess Augusta of Württemberg
Princess Augusta of Württemberg (4 October 1826 in Stuttgart – 3 December 1898, ibid.) was a daughter of King William I of Württemberg and his wife, Pauline of Württemberg.
Prince Hermann of Saxe-Weimar-Eisenach (1886–1964)
Prince Hermann of Saxe- Weimar- Eisenach( 14 February 1886 – 6 June 1964) was a member of the House of Saxe- Weimar- Eisenach.
He was heir to his relative William Ernest, Grand Duke of Saxe- Weimar- Eisenach until 1909, when he was disinherited of his royal status.
From that point onwards, Hermann was commonly referred to with the lesser style, Count Ostheim.
Princess Ernestine of Saxe-Weimar
Princess Ernestine of Saxe- Weimar- Eisenach( Ernestine Auguste Sophie; 4 January 1740 in Weimar – 10 June 1786 in Hildburghausen) was a princess of Saxe- Weimar- Eisenach and by marriage Duchess of Saxe- Hildburghausen.
Ernest Augustus II, Duke of Saxe-Weimar-Eisenach
Ernst August II Konstantin, Duke of Saxe- Weimar- Eisenach( 2 June 1737 – 28 May 1758), was a duke of Saxe- Weimar- Eisenach.
Princess Marie of Saxe-Weimar-Eisenach (1808–1877)
Princess Marie of Saxe- Weimar- Eisenach( 3 February 1808 in Weimar – 18 January 1877 in Berlin) was a princess of Saxe- Weimar- Eisenach, by birth, and, by marriage, a princess of Prussia.
She was the daughter of Charles Frederick, Grand Duke of Saxe- Weimar- Eisenach and Grand Duchess Maria Pavlovna of Russia.
Michael, Prince of Saxe-Weimar-Eisenach
Michael, Prince of Saxe- Weimar- Eisenach( born 15 November 1946) is the current head of the Grand Ducal House of Saxe- Weimar- Eisenach, as well as the most senior agnate of the entire House of Wettin.
Ernest Augustus I, Duke of Saxe-Weimar-Eisenach
Ernest Augustus I, Duke of Saxe- Weimar( German:" Ernst August I"; 19 April 1688 – 19 January 1748), was a duke of Saxe- Weimar and, from 1741, of Saxe- Weimar- Eisenach.
Prince Wilhelm of Saxe-Weimar-Eisenach
Prince Wilhelm Karl Bernhard Hermann of Saxe- Weimar- Eisenach( 21 December 1853 – 15 December 1924) was a member of the House of Saxe- Weimar- Eisenach.
Princess Pauline of Saxe-Weimar-Eisenach
Princess Pauline of Saxe-Weimar-Eisenach (Pauline Ida Marie Olga Henriette Katherine; 25 July 1852, in Stuttgart – 17 May 1904, in Orte) was the wife of Charles Augustus, Hereditary Grand Duke of Saxe-Weimar-Eisenach.
She was a daughter of Prince Hermann of Saxe-Weimar-Eisenach and Princess Augusta of Württemberg.

Question: Who is the maternal grandfather of Princess Pauline Of Saxe-Weimar-Eisenach?
Answer: William I of Württemberg