Who called for the first crusade

Pope Urban II

Explanation:

The Crusades were a series of military campaigns that had the purpose to recapture the Holy Land. The Holy Land was occupied by the Muslims, and that was not seen fondly at all by the Catholic Church. Having lot of political power in Europe, the Catholic Church managed to convince the European leaders to send their troops to fight for the Holy Land. The first person that initiated this, and managed to prompt the First Crusade, was Pope Urban II, who give this suggestion at the Council of Clermont int he year of 1095.