Manuel Hernandez (1895-1975) and Victoriano Aguado (1897-1982) met while working at a Madrid piano factory but it wasn't until the 1940s that they became involved in guitar making. In 1948 guitar maker Modesto Borreguero hired rooms in their workshop while they were still furniture restorers and this may have inspired them to become guitar makers.

Source: Guitar salon - Hernandez y Aguado