when did this religious war begin?
1096
First Crusade
The First Crusade (1096–1099) was the first of a series of religious wars initiated, supported, and sometimes directed by the Latin Church in the medieval period. The initial objective was the recovery of the Holy Land from Islamic rule. These campaigns were subsequently given the name crusades. The earliest initiative for the First Crusade began in 1095 when the Byzantine Emperor, Alexios I Komnenos, requested military support from the Council of Piacenza in the Byzantine Empire's conflict with the Seljuk-led Turks. This was followed later in the year by the Council of Clermont, during which Pope Urban II supported the Byzantine request for military assistance and also urged faithful Christians to undertake an armed pilgrimage to Jerusalem.
what was the role of individuals and groups in the first crusade To recover the Holy Land from the Islamic rule. Mobs of predominantly poor Christians numbering in the thousands,  were the first to respond. What has become known as the People's Crusade passed through Germany and indulged in wide-ranging anti-Jewish activities and massacres. where did it start? 1096 where did it start? Hungary, Rhineland
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First Crusade [SEP] Introduction
The First Crusade (1096–1099) was the first of a series of religious wars initiated, supported, and sometimes directed by the Latin Church in the medieval period. The initial objective was the recovery of the Holy Land from Islamic rule. These campaigns were subsequently given the name crusades. The earliest initiative for the First Crusade began in 1095 when the Byzantine Emperor, Alexios I Komnenos, requested military support from the Council of Piacenza in the Byzantine Empire's conflict with the Seljuk-led Turks. This was followed later in the year by the Council of Clermont, during which Pope Urban II supported the Byzantine request for military assistance and also urged faithful Christians to undertake an armed pilgrimage to Jerusalem.