Crusades
The term "crusade" used in modern historiography at first referred to the wars in the Holy Land beginning in 1095, but the range of events to which the term has been applied has been greatly extended, so that its use can create a misleading impression of coherence, particularly regarding the early Crusades. The term used for the campaign of the First Crusade was "iter" "journey" or "peregrinatio" "pilgrimage". The terminology of crusading remained largely indistinguishable from that of pilgrimage during the 12th century, reflecting the reality of the first century of crusading where not all armed pilgrims fought, and not all who fought had taken the cross. It was not until the late 12th to early 13th centuries that a more specific "language of crusading" emerged. Pope Innocent III used the term "negotium crucis" "affair of the cross" for the Eastern Mediterranean crusade, but was reluctant to apply crusading terminology to the Albigensian crusade. The "Song of the Albigensian Crusade" from about 1213 contains the first recorded vernacular use of the Occitan "crozada". This term was later adopted into French as "croisade" and in English as "crusade". The modern spelling "crusade" dates to c. 1760. Sinibaldo Fieschi (the future pope Innocent IV) used the terms "crux transmarina" for crusades in Outremer against Muslims and "crux cismarina" for crusades in Europe against other enemies of the church. Medieval Armenian term for Crusades — xacˇ‘e˘nkalk‘.
Christianity in the 11th century
The Crusades were, in part, an outlet for an intense religious piety which rose up in the late 11th century among the lay public. A crusader would, after pronouncing a solemn vow, receive a cross from the hands of the Pope or his legates and was thenceforth considered a "soldier of the Church". This was partly because of the Investiture Controversy, which had started around 1075 and was still on-going during the First Crusade. As both sides of the Investiture Controversy tried to marshal public opinion in their favor, people became personally engaged in a dramatic religious controversy. The result was an awakening of intense Christian piety and public interest in religious affairs, and was further strengthened by religious propaganda, which advocated Just War in order to retake the Holy Land from the Muslims. The Holy Land included Jerusalem (where the death, resurrection and ascension into heaven of Jesus took place) and Antioch (the first Christian city).