The millenary history of Christianity is an unalterable fact of our historic and cultural legacy. It is possible to view it from a historical perspective that is sensitive to its decisive contribution to the formation of a Christian Europe. It can also be put in a context that is sensitive to the current religious scenario, one in which Christian values appear increasingly marginalised. Or we can decide to examine this most complex and fascinating of stories through the eyes of a believer desirous of exploring the roots of his own faith. The History of Christianity of which this book is the third volume, encompasses all three approaches.