Christianity is one of the fundamental bases on which our history and cultural heritage are built. The outcome of cooperation between Italian and foreign specialists, this book retraces the key moments in the history of Christianity, from its origins to today. A religious phenomenon of extraordinary diversity, despite the divisions and splits culminating in the Protestant Reform, Christianity has maintained its own identity throughout the centuries, rooted in faith in a resurrected Christ and in his message, proclaimed to peoples around the world and adapted to different cultural contexts. A dynamic tradition, therefore, and one that contemporary society, so dangerously devoid of memory, cannot avoid addressing.