Negotiating power: the relationship between the Portuguese crown, the order of Santiago, and the diocese of Silves (1263–1536)

The kings of Portugal granted lands and jurisdictions in the Algarve to the Order of Santiago due to its cooperation in the Portuguese campaigns of expansion against Muslim domains. These jurisdictions often overlapped with those of another significant ecclesiastical authority in the region: the diocese of Algarve, centered on Silves. This study examines the evolution of the relationship between the Order of Santiago and the bishop of Algarve over nearly three centuries, relying on documents retrieved from cartularies belonging to the Portuguese knights of Santiago. Three sources constitute the core of the analysis: the Livro dos Copos (1484), the Livro das Espadas (1509), and the identically named 1538 Livro das Espadas. This investigation unveils a wide range of relevant documents, including papal bulls, grievance letters, royal charters, and agreements. The sources show a marked transformation in the power dynamics of the region: though initially positioned on relatively equal hierarchical footing, the Order of Santiago experienced a gradual process of aristocratization that, coupled with its increasing entrenchment at the royal court, elevated it to a position of heightened prominence and influence. In contrast, the diocese of Silves experienced a significant decline in power.