In this study, Joseph Duggan interprets the Cantar de mio Cid as a work that transmutes moral values first into the economic values of a gift economy, then into genealogical values. Considering the poem's distortions of history more significant than its retention of historical features, Duggan ascribes its depiction of the penurious hero who acquires wealth, power, and kinship alliances to the Castilian monarchy's preoccupations with furthering the...