Crusading

The Crusades were a series of religious wars sanctioned by the Latin Church in the medieval period, especially the campaigns in the Eastern Mediterranean with the aim of recovering the Holy Land from Islamic rule. The term "crusades" is also applied to other campaigns sanctioned by the Church, fought to combat paganism and heresy or to resolve conflict among rival Roman Catholic groups, or to gain political or territorial advantage. The term crusades itself is early modern, modelled on Middle Latin cruciatae, and has in more recent times been extended to include religiously motivated Christian military campaigns in the Late Middle Ages.

The First Crusade arose after a call to arms in a 1095 sermon by Pope Urban II. Urban urged military support for the Byzantine Empire and its Emperor, Alexios I, who needed reinforcements for his conflict with westward migrating Turks in Anatolia. One of Urban's stated aims was to guarantee pilgrims access to the holy sites in the Eastern Mediterranean that were under Muslim control, but scholars disagree whether this was the primary motivation for Urban or the majority of those who heeded his call. Urban's wider strategy may have been to unite the Eastern and Western branches of Christendom, which had been divided since their split in the East–West Schism of 1054, and establish himself as head of the unified Church. The response to Urban's preaching by people of many different classes across Western Europe established the precedent for later crusades. Volunteers became crusaders by taking a public vow and receiving plenary indulgences from the church. Some were hoping for apotheosis at Jerusalem, or forgiveness from God for all their sins. Others participated to satisfy feudal obligations, gain glory and honour, or find opportunities for economic and political gain.

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