Ernest Casimir I, Count of Nassau-Dietz
Count of Nassau-Dietz and Stadtholder of Groningen, Friesland and Drenthe
About Ernest Casimir I, Count of Nassau-Dietz
Lived 1573 – 1632 (aged 58). Ernest Casimir I, Count of Nassau-Dietz was a German and Dutch politician.
Ernest Casimir (22 December 1573 – 2 June 1632) was Count of Nassau-Dietz and Stadtholder of Friesland, Groningen and Drenthe.
Biography He was the 11th child of John VI, Count of Nassau-Dillenburg, and Countess Elisabeth of Leuchtenberg. After the death of his father, his counties Nassau-Dillenburg, Nassau-Siegen, Nassau-Dietz, and Vianden were divided among his five living sons. Ernest Casimir followed him as Count of Nassau-Dietz. In 1631, he inherited the small county of Spiegelberg near Lauenstein.
Ernest Casimir was primarily known as an outstanding military leader during the Eighty Years' War. He served under Maurice of Nassau, Prince of Orange, in the siege of the cities of Steenwijk and Oldenzaal, and Frederick Henry, Prince of Orange, during the Siege of Groenlo and the Siege of 's-Hertogenbosch. As Stadtholder of Groningen, he founded the Nieuweschans fortress in 1628. Although he owned little in Friesland, he was popular there, and people granted his heir the right to rule after his death.
He was killed by a bullet at the siege of Roermond while he was inspecting the trenches in June 1632. The hat he was wearing when he was shot and killed is now in the Rijksmuseum in Amsterdam. His son, Henry Casimir I, succeeded him as count of Nassau-Dietz and as Stadtholder of Friesland, Groningen and Drenthe.
Family In 1607, Ernest Casimir married Sophia Hedwig of Brunswick-Lüneburg, daughter of Henry Julius of Brunswick-Lüneburg. They had nine children, but two sons survived to adulthood : stillborn daughter (1608) stillborn son (1609) unnamed son (1610) Henry Casimir I, Count of Nassau-Dietz (21 January 1612 – 13 July 1640) William Frederick, Prince of Nassau-Dietz (7 August 1613 – 31 October 1664), married Albertine Agnes of Nassau Elizabeth (25 July – 18 September 1614) John Ernest (29 March – May 1617) Maurice (21 February 1619 – 18 September 1628) Elizabeth Friso (25 November 1620 – 20 September 1628)
Ancestors
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Important facts
People in Ernest Casimir I, Count of Nassau-Dietz's life
Named in this biography and alive at the same time
Contemporaries
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Frequently asked questions
Who was Ernest Casimir I, Count of Nassau-Dietz?
Count of Nassau-Dietz and Stadtholder of Groningen, Friesland and Drenthe (1574-1632)
When was Ernest Casimir I, Count of Nassau-Dietz born?
Ernest Casimir I, Count of Nassau-Dietz was born on 22 December 1573 in Dillenburg.
When did Ernest Casimir I, Count of Nassau-Dietz die?
Ernest Casimir I, Count of Nassau-Dietz died on 2 June 1632 in Roermond.
What was Ernest Casimir I, Count of Nassau-Dietz's occupation?
Ernest Casimir I, Count of Nassau-Dietz was a politician.
What nationality was Ernest Casimir I, Count of Nassau-Dietz?
Ernest Casimir I, Count of Nassau-Dietz was German and Dutch.
Sources & further reading
· Wikipedia: Ernest Casimir I, Count of Nassau-Dietz
· DBpedia: Ernest Casimir, Count of Nassau-Dietz
Cite this page
APA: Biography.guide. (2026). Ernest Casimir I, Count of Nassau-Dietz. https://biography.guide/ernest-casimir-i-count-of-nassau-dietz/
MLA: "Ernest Casimir I, Count of Nassau-Dietz." Biography.guide, https://biography.guide/ernest-casimir-i-count-of-nassau-dietz/.
Chicago: "Ernest Casimir I, Count of Nassau-Dietz." Biography.guide. https://biography.guide/ernest-casimir-i-count-of-nassau-dietz/.
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