One Catholic Nation

Is it possible, with a POD of whenever, to have all the Catholic (or, better yet, Christian, but I don't think that'd be possible for long) nations in the world united in a single federation, based on explicitly religious lines?

Bonus points if it's a theocracy under the Pope.

I can see two ways in which this could come about, the second of which is dangerously far-fetched:

a) A more sustained Muslim threat, forcing all European nations to unite in a religious union in order to better put up resistance;
b) In the future, Liberation Theology sweeps South America (perhaps in conjunction with leftist movements), and leads to a federal union of South American nations based on Catholic teachings. At the same time, reactionary Catholic movements in Europe take power as part of a backlash against modern social trends, and reform the EU. The two federations combine.

Admittedly, it's a far-fetched What If?, but I think the results would definitely be interesting.
 
Even if b) happened, there's still the Protestant / Catholic split. And protestants are dominant in two of the mightiest christian nations, USA and Britain.
 

NapoleonXIV

Banned
One way might be to have Martin Luther rejoin the Church because the Popes agree to reform. (Or maybe the really bad one dies early and is succeeded by a reformer, I think that almost happened.)

If the Church learns how to coopt its heretics, (and why not, they absorbed everything else for over a millenium, ) then it retains most of its medieval power, while still permitting the rise of secularism within its overall framwork; so that the princes have neither a locus of opposition nor even a good reason to find one.

We might get something very close to the way present day Muslim countries are run, govenments of varying degrees of secularism/theocracy but all saying they rule in the Church's name

The rise of Democracy here might even be supported by a Church seeking to reassert itself under increasing domination by Princes using it to justify their autocratic rule. Liberation theology would then become the dominant dogma, with elected pastors, bishops and cardinals, all chosen from people entering the priesthood as today we enter the law if you want to go into politics.
 
Even if b) happened, there's still the Protestant / Catholic split. And protestants are dominant in two of the mightiest christian nations, USA and Britain.

Well, the second scenario depended upon liberation theologist regimes coming to power in only nations that are majority Catholic. The Protestant nations would be left out. I agree, it's still a far-fetched scenario.

NapoleonXIV's scenario, though, looks very interesting-I just question the ability of the church to prevent a major schism, since certain doctrinal issues were bound to cause problems sooner or later (the five solas, for instance). It would make a very interesting timeline, though.
 
Well, WI there were certain longer-standing political effects for unity from such Christian revivals as in Wales 1904 and Azusa Street 1906, or poss even earlier with the Moravian community's renewals in Bohemia under Count von Zinzendorf in the 1720s ? Could such evcents, if lasting longer, have led to the establishment of discrete unified Christian communities ?
 
Well, WI there were certain longer-standing political effects for unity from such Christian revivals as in Wales 1904 and Azusa Street 1906, or poss even earlier with the Moravian community's renewals in Bohemia under Count von Zinzendorf in the 1720s ? Could such evcents, if lasting longer, have led to the establishment of discrete unified Christian communities ?
 
The easiest way to get a single European Christendom is to work out a different resolution to lay investiture. If it became normal for rulers to give feudal holdings to clergy then the Church could develop into a tighter confederacy.

Lay investiture was attractive to the secular rulers because clergy didn't have legitimate children, which meant that the lands given out returned to the liege to give out again, though traditions quickly determined that such and such a holding was always given to the Bishop of wherever. The Church objected because of likely conflicts of interest and struggles with the appointment of clergy. If instead the Church had allowed lay investiture, in fact encouraged it, but maintained control of the appointments, the power would gradually shift.

Nationalism is a modern occurrence. In the 12th century, the closest thing to a nationality most Europeans recognized was Christianity; they saw themselves as members of their local community first, Christians second, and only if pressed would they call themselves French or German, neither of which nation solidified into its modern shape anytime near the 12th century. The Church already interfered in the affairs of countries, ending wars and deciding heredity, giving more holdings to clergy could only result in greater Church control over secular politics.

Later on this would give greater motivation to the Protestant Reformation, but also give them fewer places to take hold.
 
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