Luis Dionisio de Lezama Leguizamón y Sagarminaga (1865-1933) was a Spanish entrepreneur, Vascologist and politician. As a businessman he kept developing the family-owned mining conglomerate, which controlled part of iron ore, carbon, fluorite, anhydrite and plaster exploitation in Vascongadas and Asturias. As a linguist he was a longtime executive of Sociedad de Estudios Vascos, owned one of the largest collections of Basque literature and contributed few scientific works himself. As a politician he supported the Traditionalist cause, first as a Carlist, in 1919-1931 as a breakaway Mellista, and then again as a Carlist; in the early 1930s he held the provincial party jefatura in Biscay. Family and youth The Lezama family is among the oldest in Vascongadas, traced back to the 12th century; one branch settled in Biscay. Some of its representatives rose to high posts in Madrid; the Biscay branch, apart from having been among largest landholders in the region, specialized as merchants and were army suppliers. The great-grandfather of Luis, Juan Antonio de Lezama Jugo, was the first one to call himself Lezama Leguizamón; the surname incorporated the name of a related distinguished branch, which was about to extinguish. The grandfather of Luis, Gregorio Lezama Leguizamón Eguia (1781-1857), was the one who transformed the family into business tycoons. Though one of the largest terratenientes in Biscay, he turned major protagonist of industrial revolution in the province. Initially owner of an ironworks mill, he engaged in industrial-scale iron mining, made possible thanks to introduction of Bessemer converters and the richest vein of iron ore in Europe, located in Biscay. In the mid-19th century he obtained a number of mining concessions and in the 1850s formed an emergent new social class of industrial moguls. The youngest son of Gregorio, Manuel Lezama Leguizamón Aldama (1817-1884), inherited part of the family business and developed it further on. He kept obtaining new mining concessions, counted among “destacados miembros de las élites bilbaína” and owned one of the most successful industrial conglomerates in Biscay. He married María Concepción Sagarminaga Zabala, descendant to a less affluent, but prestigious Basque family. The couple had 2 sons, Luis born as the younger one. Nothing is known about his early education; later he was prepared to take over the family business and at unspecified time, though most likely in the late 1880s, he studied engineering in Barcelona. Following the death of their father, Manuel and Luis set up