During the high medieval period in Europe — a time when the continent’s population increased rapidly, bringing about great social and political change — Pope Urban II sparked a religious war when he urged Christians to recapture the Holy Land, a region that lies between the Jordan River and the Mediterranean Sea and is held sacred among Christians, Jews and Muslims, particularly the holy city of Jerusalem. The result was a series of military campaigns that lasted from 1095 to 1291, known today as the Crusades.  Photo credit: Photo 12/ Universal Images Group via Getty ...Read More