At the request of the Catholic pope, Christians of the Middle Ages sometimes formed huge armies and traveled to the Middle East. There, they battled the Muslims for control of a small area known as the Holy Land. Even the powerful responded to the pope's call to arms. Among them was King Richard I of England, who swore he would fight to win Christians the right to visit the holy city of Jerusalem. In KING RICHARD THE LIONHEARTED AND THE CRUSADES IN WORLD HISTORY, authors Katherine M. and Craig A. Doherty trace the history of the religious wars fought for control of the land considered holy by Muslims and Christians alike. Highlighting the role of Richard I of England, known to history as Richard the Lionhearted for his brave military leadership, the authors examine the dramatic struggle between the crusaders and their Muslim opponents.