Gotthard Kettler
Gotthard Kettler, Duke of Courland (also "Ketteler", ; 2 February 1517 – 17 May 1587) was the last Master of the Livonian Order and the first Duke of Courland and Semigallia.
John Albert I, Duke of Mecklenburg
John Albert I, Duke of Mecklenburg, in older literature known as" John" or" Johann"( 23 December 1525 – 12 February 1576), was the reigning Duke of Mecklenburg- Güstrow from 1547 to 1556 and of Mecklenburg- Schwerin from 1556 to 1576.
In 1549 John Albert I saw to it that the parliament of Mecklenburg carried through the Reformation for the entire Duchy.
Henry Borwin II, Lord of Mecklenburg
Henry Borwin II, Lord of Mecklenburg( 1170 – 5 June 1226) was a member of the House of Mecklenburg, was a Prince of Mecklenburg from 1219 to 1226 and Lord of Rostock( 1225- 1226).
Anna of Mecklenburg
Anna of Mecklenburg (14 October 15334 July 1602), was a Duchess consort of Courland by marriage to the Duke of Courland, Gotthard Kettler.
She was the daughter of Albrecht VII, Duke of Mecklenburg and Anna of Brandenburg.
Anna is the first woman in Livonia whose life story is entirely historically confirmed.
Anna of Brandenburg, Duchess of Mecklenburg
Anna of Brandenburg (1 January 1507 – June 19, 1567 in Lübz) was a Duchess consort of Mecklenburg.
Theodred II (Bishop of Elmham)
Theodred II was a medieval Bishop of Elmham.
The date of Theodred's consecration unknown, but the date of his death was sometime between 995 and 997.
Princess Louise of Saxe-Gotha-Altenburg (1756–1808)
Princess Louise of Saxe- Gotha -Altenburg,( born 9 March 1756 in Roda, Duchy of Saxe- Gotha- Altenburg; died 1 January 1808 at Schloss Ludwigslust in Ludwigslust, Duchy of Mecklenburg- Schwerin) was Duchess consort of Mecklenburg- Schwerin through her marriage to Frederick Francis I, Grand Duke of Mecklenburg, Louise was also a member of the House of Mecklenburg.
Borwin, Duke of Mecklenburg
Borwin, Duke of Mecklenburg( given names:" Georg Borwin Friedrich Franz Karl Stephan Konrad Hubertus Maria"; born 10 June 1956) has been the head of the House of Mecklenburg- Strelitz since 1996 and of the entire House of Mecklenburg since 2001.
The death of Friedrich Franz, Hereditary Grand Duke of Mecklenburg- Schwerin the last male member of the House of Mecklenburg- Schwerin on 31 July 2001 made Strelitz the only remaining line of the House of Mecklenburg, which ruled in Mecklenburg until 1918.
Borwin and his sons, Alexander and Michael, are the only known surviving legitimate male- line descendants of the medieval princely dynasty descended from Niklot of the Obotrites, which has included King Albert of Sweden.
Duchess Gustave Caroline of Mecklenburg-Strelitz
Duchess Gustave Caroline of Mecklenburg- Strelitz( 12 July 1694 – 13 April 1748) was a daughter of Adolphus Frederick II, Duke of Mecklenburg and Princess Maria of Mecklenburg.
John VI, Duke of Mecklenburg
John VI, Duke of Mecklenburg( 1439 – 1474) was a Duke of Mecklenburg.

Question: When was Anna Of Mecklenburg's husband born?
Answer: 2 February 1517