This conflict perhaps deserves the title of the First World War.  This bitter two hundred year long struggle would outlast the Hundred Years War which it preceded.  It would pit ideologies and religions against one another with devastating impact.  It would change the nature of leadership, redefine the rights of kings and create the science of Logistics.  It would be the inventor of terrorism and see the earliest known incidents of antisemitism.  It would echo through the ages, right into the heart of the 21st Century.