Louis Frederick, Duke of Württemberg-Montbéliard
Louis Frederick of Württemberg- Montbéliard( 29 January 1586 in Montbéliard – 26 January 1631 in Montbéliard) was the founder of a cadet line of the House of Württemberg known as the Dukes of Württemberg- Montbéliard.
Louis Frederick of Württemberg was born at Montbéliard Castle as the fifth child and second son of Duke Frederick I of Württemberg, and princess Sibylla of Anhalt.
Barbara Sophie of Brandenburg
Barbara Sophia of Brandenburg (16 November 1584 – 13 February 1636) was duchess of Württemberg by marriage to Duke John Frederick of Württemberg and acted as regent of the Duchy of Württemberg for their minor son, Duke Eberhard III of Württemberg, in 1631-1633.
She was the daughter of the Catherine of Küstrin (1549–1602) and Elector of Joachim Frederick of Brandenburg.
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 Frederick of Württemberg
Prince" Frederick" Charles Augustus of Württemberg( 21 February 1808 – 9 May 1870) was a General in the Army of Württemberg and the father of William II of Württemberg.
Frederick was a member of the Royal Family of Württemberg and a Prince of Württemberg.
Wilhelm, Duke of Urach
Count Friedrich Wilhelm Alexander Ferdinand of Württemberg, 1st Duke of Urach( 6 July 1810, in Stuttgart – 17 July 1869, in Schloss Lichtenstein), was the son of Duke Wilhelm of Württemberg( 1761 – 1830), younger brother of King Frederick I of Württemberg, by his morganatic wife, Baroness Wilhelmine von Tunderfeldt- Rhodis( 1777 – 1822), who had married in 1800.
He was the first Head of the House of Urach.
Wilhelm served as a cavalry officer in the army of the then- independent Kingdom of Württemberg.
He also tested cannon for the Army of Württemberg, some of which can still be seen at Lichtenstein Castle, which he substantially rebuilt in the 1840s.
He was inspired by the romantic historical novel" Lichtenstein" by Wilhelm Hauff( 1826).
Hauff was in turn inspired by the works of Walter Scott.
He was created Duke of Urach on 28 March 1867, with the style of Serene Highness.
Wilhelm was a junior member of the royal family of Württemberg.
He was a nephew of King Frederick( d. 1816), and was a first cousin of King William I of Württemberg( ruled 1816 – 1864).
Princess Catherine of Württemberg
Princess Catherine Frederica Charlotte of Württemberg (Stuttgart, 24 August 1821 – Stuttgart, 6 December 1898) was a daughter of William I of Württemberg and Pauline Therese of Württemberg.
She was the mother of William II of Württemberg.
Duke Alexander of Württemberg (1804–1885)
Duke Alexander Paul Ludwig Konstantin of Württemberg( 9 September 1804, Saint Petersburg – 4 July 1885 Tüffer) was the father of Francis, Duke of Teck and the grandfather of Mary of Teck, wife of George V of the United Kingdom.
His father was Duke Louis of Württemberg, brother of King Frederick I of Württemberg and Empress Maria Feodorovna of Russia.
His mother was Princess Henriette of Nassau- Weilburg, a great- granddaughter of George II of Great Britain through his eldest daughter Anne, Princess of Orange.
Pauline Therese of Württemberg
Pauline of Württemberg (4 September 1800 – 10 March 1873) was a daughter of Duke Louis of Württemberg and Princess Henriette of Nassau-Weilburg.
She married her first cousin King William I of Württemberg and was his consort.
Duke Eugen of Württemberg (1758–1822)
Duke Eugen of Württemberg( 21 November 1758 – 20 June 1822) was a German prince.
He was the brother of Frederick I of Württemberg
Christoph, Duke of Württemberg
Christoph of Württemberg, Duke of Württemberg (12 May 1515 – 28 December 1568) ruled as Duke of Württemberg from 1550 until his death in 1568.

Question: Who is Princess Catherine Of Württemberg's maternal grandfather?