This thesis is a study of the reasons for the failure of the Third Crusade to achieve its stated objectives, despite the many advantages with which the venture began. It is proposed herein that the Third Crusade—and by extension all of the previous and subsequent Crusades—were destined to fail because of structural disadvantages which plagued the expeditions to the Holy Land. The Christians in the Holy Land were not selfsufficient, and they depended on an extensive amount of aid from Europe for their existence, but the Christians of Europe had their own goals and concerns which did not allow them to focus on building a stable kingdom in the Holy Land. For European Christians, crusading was a religious obligation, and once their vows were fulfilled, they no longer had any desire to remain in the Levant. Although the Crusaders did score some short-term victories over their Muslim adversaries, the Christian presence in the Holy Land was unsustainable, for the Crusades—from the European perspective—were a religious movement without a tangible, long-term political objective, and given those circumstance, any crusade would be unsuccessful.

This thesis focuses on the politics of Antipope Victor IV and his successors Paschal III, Calixtus III and Innocent III, who were the opponents of Alexander III since the schismatic elections of 1159. The aim is to analyse the political thinking and actions of the antipopes, with an emphasis on the political relations of Victor IV. The thesis is divided into six thematic sections. The first deals with the pre-election developments and the election of 1159 itself. The second considers their position in relation to Alexander III, while the third turns to the papal-imperial policy and examines the relationship between the antipopes and Emperor Frederick Barbarossa. The fourth section discusses the status and relations of the antipopes outside the Holy Roman Empire. The penultimate chapter examines the attitude of the imperial clergy to the pontificates of the antipopes as well as the obedience of the imperial monasteries, according to papal documents. The final chapter constructs biographies of the antipopes, focusing on the period before their pontificates.