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In this Spanish name, the first or paternal surname is Fernández de Heredia and the second or maternal family name is Gaztáñaga.
Enrique Fernández de Heredia Gaztáñaga was a military commander in the Spanish Civil War fighting on the Republican side. He was a commander of artillery in the Spanish Republican Army before the war and was promoted to command the 31st Division. He later commanded the XVIII Corps at Brunete and Teruel.