Charles Eugène de Croÿ (1651–1702) was the son of Jacques Philippe de Croÿ-Roeulx and Johanna Catharina van Bronckhorst. He married Wilhelmina Juliana van den Bergh, who was 13 years older than he was. He fought in the 1676 Battle of Lund on the Dano-Norwegian side, then for the Austrian army in the liberation of Vienna in 1683 and the attack on Belgrade in 1690. He was promoted to imperial field marshal for his exceptional work on the Petrovaradin Fortress in 1662. He sat as Duke of the House of Croÿ As a member of the Russian army in the Battle of Narva in November, 1700, he was taken prisoner and died as a prisoner in 1702 in Reval (Tallinn). He lived as a prisoner for two years.
Mummification
He died as a prisoner of war in 1702.

On demand of his creditors, his body, which rested at St. Nicholas' Church, was not buried. None of his friends or family would pay for his funeral following his death, so his body eventually naturally mummified and was put on display at the St. Nicholas' Church in Tallinn Estonia for approximately 190 years.
References
Bushkovitch, Paul (2001). Peter the Great: The Struggle for Power, 1671-1725. Cambridge, England: Cambridge University Press. ISBN 0-521-80585-6.
Schuyler, Eugene (2004). Peter the Great. Part One. Kessinger Publishing. ISBN 1-4179-7142-8.