In the Middle Ages, efforts were made in order to establish a single Christian state of Pan-Christianity by uniting the countries within Christendom. [1] [2] Christian nationalism may have played a role in this era in which Christians felt the impulse to recover lands in which Christianity flourished. [3] After the rise of Islam, certain parts of North Africa, East Asia, Southern Europe, Central Asia, and the Middle East lost Christian control. [4] In response, Christians across national borders mobilized militarily and a "wave of Christian reconquest achieved the recovery of Spain, Portugal, and southern Italy, but was unable to recover North Africa nor—from a Christian point of view, most painful of all—the Holy Land of Christendom." [4]
Major religions in the past, especially Christianity, have attempted to include all their adherents in a large union, but they have not been successful. Throughout most of the Middle Ages in Western Europe, attempts were made again and again to unite all the Christian world into a kind of Pan-Christianity, which would combine all Christians in a secular-religious state as a successor to the Roman Empire.
Throughout the better part of the Middle Ages, elaborate attempts were made to create what was, in effect, a Pan-Christianity, an effort to unite "all" the Western Christian world into a successor state of the Roman Empire.