Luis’ paternal family was related to Old Castile; one of his ancestors gained recognition as member of the Cura Merino unit, fighting the French during the War of Independence; he served under the same commander also during the First Carlist War. Later on the family found itself on the descendant path and Luis’ grandparents were referred to as "laboradores modestos". His father, Mariano Hernando Ruiz (1861-1913), originated from Riaza in the province of Segovia; he studied medicine but upon graduating has never practiced; instead, he made a living by trading arts, mostly paintings and sculptures. Heavily engaged in preparing the Spanish pavilion for the Paris Exposition Universelle of 1889, apart from presenting art he also co-ordinated works related to construction of a bullring in the Trocadero park. He has never made it to the affluent bourgeoisie strata and back in Madrid suffered financial problems, living first at Calle Ancha de San Bernardo and then at Calle Lista. Mariano Hernando married Maria Cuadrado, with whom he had 3 children. Upon her premature death he remarried with Luisa Larramendi Serrano, also a madrileña though of Alavese origins. The couple had 6 children, Luis born as the oldest of the siblings and the only son.