Princess Thyra of Denmark (1880–1945)
Princess Thyra of Denmark and Iceland (Thyra Louise Caroline
Amalie Augusta Elisabeth; Copenhagen, 14 March 1880 – Copenhagen, 2 November 1945) was the sixth child and third daughter of Frederick VIII of Denmark and his wife, Princess Louise of Sweden and Norway.
She was named for her paternal aunt, Princess Thyra of Denmark.
She died unmarried and without issue.
Princess Louise of Denmark (1726–1756)
Louise of Denmark and Norway (19 October 1726 – 8 August 1756) was a Danish and Norwegian princess, the daughter of King Christian VI of Denmark and his wife Sophie Magdalene of Brandenburg-Kulmbach.
Following her marriage to Ernest Frederick III, Duke of Saxe-Hildburghausen, she became Duchess of Saxe-Hildburghausen.
Louise of Sweden
Louise of Sweden( Louise Josephine Eugenie; 31 October 1851 – 20 March 1926), was Queen of Denmark as the spouse of King Frederick VIII.
She was the only surviving child of Charles XV of Sweden and his consort, Louise of the Netherlands.
She was the mother of both King Christian X of Denmark and King Haakon VII of Norway.
Ernest Frederick III, Duke of Saxe-Hildburghausen
Ernst Frederick III Karl, Duke of Saxe-Hildburghausen (10 June 1727 in Königsberg in Bayern – 23 September 1780 in Seidingstadt), was a duke of Saxe-Hildburghausen.
Princess Louise of Denmark (1750–1831)
Princess Louise of Denmark and Norway( 20 January 1750 – 12 January 1831) was born to Frederick V of Denmark and Louise of Great Britain.
Her eldest daughter, Marie of Hesse- Kassel, was the wife of Frederick VI of Denmark.
Louise of Hesse-Kassel
Louise of Hesse-Kassel (7 September 1817 – 29 September 1898) was Queen of Denmark by marriage to King Christian IX of Denmark.
Princess Louise of Denmark (1875–1906)
Princess Louise of Denmark(" Louise Caroline Josephine Sophie Thyra Olga")( 17 February
1875 – 4 April 1906) was a Danish princess, the third child and oldest daughter of Frederick VIII of Denmark and his wife, Princess Louise of Sweden and Norway.
Princess Louise of Prussia (1808–1870)
Princess Louise of Prussia (1 February 1808 – 6 December 1870) was the third surviving daughter and ninth child of Frederick William III of Prussia and Louise of Mecklenburg-Strelitz.
Pieter van Vollenhoven
Pieter van Vollenhoven Jr.( born April 30, 1939) is the husband of Princess Margriet of the Netherlands and a member, by marriage, of the Dutch Royal House.
Princess Dagmar of Denmark
Princess Dagmar of Denmark(" Dagmar Louise Elisabeth"; 23 May
1890 – 11 October 1961) was the youngest child and fourth daughter of Frederick VIII of Denmark and his wife, Princess Louise of Sweden and Norway.

Question: What is the place of birth of Princess Louise Of Denmark (1726–1756)'s husband?
Answer: Königsberg in Bayern