The Song of the Cid is the oldest surviving epic poem in Castilian Spanish and one of the foundational works of Spanish literature. The poem recounts the life and exploits of Rodrigo Díaz de Vivar, known as El Cid, a noble warrior who is unjustly exiled by King Alfonso VI of Castile.
Forced to leave his home and family, the Cid gathers loyal followers and begins a series of military campaigns across the Iberian Peninsula. Through courage, strategy, and leadership, he defeats rival armies and gains wealth and honor while gradually restoring his reputation. His greatest triumph comes with the conquest of Valencia, where he establishes his rule and secures prosperity for his followers. Eventually, the king reconciles with him and restores his standing. The poem concludes with the marriages of the Cid's daughters to noblemen, but their husbands later mistreat and abandon them, leading the Cid to seek justice before the royal court. Blending historical events with heroic legend, the epic celebrates loyalty, honor, bravery, and the struggle for personal dignity. The Song of the Cid offers a vivid portrayal of medieval Spanish society and remains a cornerstone of Hispanic literary tradition.

The author of The Song of the Cid is unknown. The poem was composed around the early thirteenth century and preserved in a manuscript copied in 1307. It reflects the oral epic traditions of medieval Spain and celebrates the legendary deeds of the historical warrior Rodrigo Díaz de Vivar.