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In page Oskar von Hindenburg:

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Oskar von Hindenburg was born in Königsberg, East Prussia (present-day Kaliningrad, Russia), the only son of Paul von Hindenburg (1847–1934) and his wife Gertrud Wilhelmine (1860–1921). He had two sisters, Irmengard Pauline (1880–1948) and Annemarie (1891–1978). In 1921, he married Margarete von Marenholtz (1897–1988), the couple had four children.