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In page Paul von Hindenburg:

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In 1873, he passed the highly competitive entrance examination for admission to the Kriegsakademie in Berlin.[1] After three years of study, his grades were high enough for an appointment with the General Staff. He was promoted to captain in 1878 and assigned to the staff of the II Corps. He married the intelligent and accomplished Gertrud von Sperling (1860–1921), daughter of General Oskar von Sperling, in 1879. The couple would have two daughters, Irmengard Pauline (1880) and Annemaria (1891), and one son, Oskar (1883). Next, he commanded an infantry company, in which his men were ethnic Poles.[citation needed]