Final answer:
The idea that medieval people primarily identified themselves through ethnicity first and religion second is false, as religion was the central defining trait of medieval societies. Additionally, the Spanish Reconquista was both a military and religious endeavor affirming the statement as true.
Step-by-step explanation:
The statement that medieval people defined themselves first by their ethnic origins and second by their religious orientations is false. During the early Middle Ages, shared cultural traits, particularly religion, were the main defining characteristics of societies. For instance, religion played a central role in intellectual and spiritual institutions and in the shaping of the social hierarchy and state identity. Medieval Europe was greatly influenced by this cohesion of religious identity.
In the context of the Spanish Reconquista, the effort to retake the Iberian Peninsula was indeed a military and religious action, which makes the correct answer to exercise 2.1.3 true. The Reconquista was a centuries-long series of battles by Christian states to recapture territory taken by Muslims (Moors). It was motivated not just by the desire to reclaim territory, but also by religious zeal, as the Christians sought to spread their faith and diminish the influence of Islam in the region.