Although we think of “the Crusades” as the numbered (anachronistically) series of Christian military expeditions in the Middle East (and North Africa, and Greece that one time) that took place in the 11th-13th centuries, the Crusading movement actually encompassed much more than that. The Reconquista in Iberia was, for a time, treated as a Crusade, for example. There was also the “Alexandrian Crusade” of 1365, which brought Christian fighters back to the Middle East to sack the city of Alexandria. Crusades didn’t even have to involve Muslims. The Albigensian Crusade in the early 13th century targeted the Cathars, considered heretics by the Church, and the Northern Crusades in the 12th and 13th centuries targeted the last pagan populations in Europe (mostly in the Baltics and Finland). There were also “Crusades” that were called to defend Christendom from Muslim—usually Ottoman—invasion. The 1396 Crusade of Nicopolis (which is often called the “Battle of Nicopolis” since the enterprise collapsed after just one engagement), was one such effort.
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