Neutron

This alternate timeline is unique in that both Homeline and Centrum were firmly convinced that in 1936 the other had intervened in Neutron’s General War, via the sudden and strategic use of neutron bombs against the Frankish Empire. Certainly both sides had some reason to think so; the crippling of the Franks gave the English-speaking British Empire and the USNA more power in the postwar period (which would please Centrum), while ending a fairly nasty regime that seemed determined to reduce Eurasia to a series of slave states (which would please Homeline). However, a recent operation managed to prove to both organizations that neither of them can take ‘credit’ for the intervention.
Which leads to the question: then who did?
==Background==
Please note: Napoleon II (1811-1872) was not in any way an awful human being. Neither was his cousin and crony Prince Louis-Napoléon of France (1808-1876); under their supervision, the Second French Empire soon dominated Continental Europe, defeating the Austrians in 1859 and the Prussians in 1870. From Paris the French ruled over lands on four continents, and might have managed five if poor Prince Maxmilian had managed to hold onto Mexico. Still, it was a golden age for the French, and when Napoleon II died suddenly in 1872 the entire country sincerely mourned him.
Under different circumstances -- such as a worthy heir -- Europe might have avoided a lot of trouble for the next century. Unfortunately, Napoleon II’s son Napoleon III (1840-1913) was harsh, often cruel, and had a taste for power that was only matched by his ability to govern. It was long rumored that Napoleon III had his own father and uncle poisoned in order to first rule, and then to rule solely; and during his reign the French Empire ruthlessly conquered Italy and Germany. Ironically, Napoleon III ultimately grew heavily reliant on the Prussians that his father had defeated, to the point of renaming his realm the Frankish Empire in 1905. 
When Napoleon III died in 1913 (of natural causes) he left to his own heir Napoleon IV (1862-1936) an increasingly regimented and warlike state that soon clashed with the Austro-Hungarian Empire. The Frankish-Austrian War took place between 1915-1917, and ended with the Franks conquering Austro-Hungary outright; the Ottomans then made the fatal mistake of attempting to take advantage of the chaos, only to be dismembered between the Franks and Imperial Russia from 1918 to 1920.
There was no lasting peace, of course: in 1933 the Frankish Empire declared war on all of the remaining continental countries in Western Europe, conquering the Low Countries and Scandinavia in alarmingly fast campaigns, then forcing the Spanish and Portuguese into humiliating treaties in 1934. War with the Russians naturally followed in 1935, with Frankish armies deep in Ukraine by 1936. The war ground slowly, but inexorably in the Franks’ favor, and the reorganization of the conquered territories was both horrible and efficient; the end of the war was a foregone conclusion. 
Or at least it was up until February 6th, 1936, when the heart of the Frankish Empire was suddenly cut out of it. Homeline, based on the evidence it could find a decade later, determined that the explosives used were mid-level neutron bombs, set for airbursts and at a time to maximize the chances for a governmental decapitation strike. The civilian targets were Versailles, Lyons, Marseilles, Berlin, Graz, Prague, Vienna, Cologne, Hamburg, and Budapest; and while two of the most forward elements of the Frankish armies were struck, the majority of the neutron bombs used on military targets hit rear supply areas, guaranteeing utter chaos on the front (which collapsed within a week anyway).
The civil war that followed was remarkably brutal, at levels not seen since the Thirty Years’ War, but most of the formerly-conquered states were able to at least secure their own borders again (typically with either British or Russian ‘help’). The core areas of the Frankish Empire themselves quickly broke down into a stereotypical crazy quilt of kingdoms, revolutionary republics, grand duchies, and other pocket realms that still persist, twenty years later. There is constant conflict, but mostly at a level that mercenary companies find optimal.
Geopolitically, the British and the Russians are still functional empires (note that Britain was not gutted by continental wars in this timeline); the Japanese have a very free hand in East Asia and the USNA (which conquered Mexico in 1915, after one too many Frankish schemes to use that country as a cat’s-paw) more or less dominate the Americas. On the bright side, there’s no equivalent of World War II brewing. On the dark side, large parts of Eurasia are still unpleasant places to live, even though the war’s been over for twenty years.
Oh, and every Great Power has neutron bombs now. They don’t know who dropped the original ones, but they’ve all made sure to have independently worked out how to make their own. Which is probably another reason why there’s not been another major war.
==Outworld Involvement==
Centrum discovered Neutron in 1945 (about six months after Homeline did), and both sides promptly assumed that the other one had had some sort of highly embarrassing screwup that led to mass murder and an internal coverup. It was a reasonable assumption, particularly if one thinks that your enemy are particularly horrible human beings anyway; and, truth be told, there have been incidents where out-time nukes have been used to secure a timeline. Nobody’s hands are perfectly clean.
However, in local year 1957 it came out (as part of a Homeline mole hunt) that Centrum legitimately had no role in dropping the 1936 neutron bombs. Centrum later discovered the same about Infinity (that mole hunt had been called for a reason), and the situation was deemed fraught enough to justify a rare field summit meeting between Infinity and Interworld. Since then, there’s been a tacit truce on Neutron.
Why? Because if Homeline didn’t do it, and Centrum didn’t do it, and the locals sure as heck didn’t do it, then somebody else from another dimension must have done it. Apparently randomly, because there’s no sign of a third out-time organization working on Neutron -- but that needs to be checked, and right quickly, too. Which means, no shenanigans with the other side. Share information, and share resources, and keep things civil.
For the record: both Homeline and Centrum are following this reasonably well. Also for the record: both sides are assuming that the other is cheating, as much as they can. Can’t imagine how that lack of trust is going to hinder joint operations, though.
==References==
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Category:Reality Classification
Category:Quantum 6
Category:No Mana