Diego de Saavedra y Fajardo
Saavedra was head of the Spanish delegation until he lost favour at court and was replaced by Peñaranda. He was an experienced diplomat but also a learned humanist; he and Chigi read their own poetry to each other. Saavedra wrote several well-regarded books on politics and diplomacy, including “Gothic Crown” (tracing the lineage of Spanish kings) and “Follies of Europe” (Locuras de Europa), which tried to show that governments were ignoring their own interests. (As an example, Poland was a natural enemy of Sweden and should lend troops to the Empire to defeat them, or Sweden would return to fight Poland after the war with the Empire was over — a remarkably prescient comment.) He is best known for “Idea of a Political Christian Prince,” which was a sort of manual on how to govern effectively according to Christian principles.