There is scant evidence about the early part of Mena's life, but most modern scholars agree that he was born at Córdoba, Spain, his father died shortly after his birth, and his mother a few years later.
During this trip and a later one to Florence, Mena appears to have been seeking ecclesiastical benefices; however, both attempts were fruitless and each was followed by a marriage, first to a supposed sister of García y Lope de Vaca and, secondly, to Marina Méndez, more than 20 years his minor.
Mena continued in the role of cronista real under Enrique IV de Castilla until his death at Torrelaguna in 1456, although he apparently did not write any chronicle.
His activities at the court of Juan II brought him into contact with many important figures; the most significant friendship that resulted was with Íñigo López de Mendoza.
In his imitation of classical and medieval sources, such as Dante, Mena helped stretch the capabilities of a fledgling Castilian literary tradition, paving the way for later poets.
It is largely due to the awkwardness and weight of his style and lexicon that his influence began to wane in the seventeenth and eighteenth centuries and fell out of favor with nineteenth-century critics.
Modern critics have reinstated Mena's importance to Spain's literary history and consider him to be one of the three major poets of the fifteenth century, along with Íñigo López de Mendoza and Jorge Manrique.
It is possible to interpret the Reconquista and national unity as the principal themes of the poem; one of Mena's lesson seems to be that internal strife is a vice that hinders the Christian reconquest of Spain.