Guest Post: France Cedes Alsace (and not Lorraine) under Treaty of Frankfurt

This post originally appeared on Today in Alternate History.

August 22, 1871 - France Cedes Alsace under Treaty of Frankfurt 

"If France persists in wanting the republic, which would be a bad neighbor for Germany, we will persist with our territorial demands" ~ OTL Chancellor Bismarck in the aftermath of the Franco-Prussian War

Culturally and dialectically German, Alsace had been French territory for over two and a half centuries. This occupation was to keep it out of the hands of the Spanish Habsburgs, despite it being heavily contested between France and various German states in wars and diplomatic conferences. 

The latest external threat had come from the Prussians who had inflicted a series of defeats that brought the Second French Empire to the verge of disaster. Not needing to be reminded that it was Marshall Blücher's Prussians that turned the tide at Waterloo, the French Emperor was determined to seek a different fate from his illustrious uncle. After yet another defeat at Beaumont-en-Argonne, Napoleon III decided that instead of simply leading his troops in a charge to break out, it was time to find a new way to fight.

This tactic resulted in the onset of Trench Warfare at Sedan. Although France had avoided a military collapse, the victory was German's. Nevertheless, Wilhelm's territorial ambitions were sharply diminished. Bismarck wisely cautioned against the collapse of Bonapartist rule because it would likely backfire by creating a vengeful republican neighbor. 

Napoleon III reluctantly ceded the disputed territory of Alsace to Kaiser Wilhelm I under the provisions of the ill-fated Treaty of Frankfurt. Consequently, Lorraine remained in French hands, Napoleon III remained on the throne, and talk of a Capetian restoration or a republican overthrow came to naught.

Trouble was still around the corner because Napoleon refused to recognize the new German Empire. Despite the peaceful intentions of elder statesmen, the separation of Alsace-Lorraine was to open the door to a second Franco-Prussian War fought by their successors. Napoleon IV succeeded his father in 1873, whose dying words were, "Be brave as we were at Sedan." During his reign the Second French Empire invested heavily in efficient railway infrastructure that enabled troops to be rushed to the border and dig in with only hours' notice.

In response, the Germans developed a military machine with the intent of breaking trench defenses. The "kampfwagen" ("battle wagon") was an armored motorized transport powered by steam. After Bismarck was fired by Wilhelm II in 1890, the new king paid a needlessly provocative visit to Strasbourg that humiliated France's national prestige. His assassination by a French-speaking Alsatian stoked the cinders of the still-burning dispute and triggered the outbreak of a devastating conflict in Europe. New diesel-powered kampfwagene stormed France, conquering Paris in a matter of weeks.

Wikipedia Note:

In reality, following an armistice with France, the Treaty of Frankfurt was signed on 10 May 1871, giving Germany billions of francs in war indemnity, as well as most of Alsace and parts of Lorraine, which became the Imperial Territory of Alsace-Lorraine. French determination to regain Alsace-Lorraine and fear of another Franco-German war, along with British apprehension about the shifting balance of power towards Germany, were among the factors that caused World War I.

Jeff Provine's Note:

In reality, Napoleon III ordered several attempts at breaching the German siege at Sedan. By September 2, when it became obvious that they were trapped, Napoleon surrendered himself and his massive army. The French Empire collapsed, and the resulting Treaty of Frankfurt would unify Germany under the rule of Wilhelm. Napoleon III would be exiled to London, where he would die in 1873 with his last words, "We were not cowards at Sedan, were we?"

 Provine's Scenario Addendum:

After the fall of Paris, France faced peril not only from German invasion but from republicanists suggesting the imperial government-in-exile at Orleans should be removed. Napoleon IV had successfully created a line of defense in the Loire River, blowing bridges and ensuring water flowed deeply enough to flood any potential diesel engines trying to cross. With modern warfare still being largely experimental, the emperor was open to ideas, prompting the Philippe, the pretender Duke of Orleans, to present a battle plan. Philippe had come to France illegally in 1886, breaking the law of exile, and lived in Switzerland when not adventuring in Africa and Asia.

Following Philippe's strategy of semi-scorched earth, French soldiers attacked the German supply lines and destroyed all possible sources of diesel fuel. Soon the German army found itself trapped far behind enemy lines with kampfwagene that were little more than artillery placements already low on ammunition. German attempts to free the army in Paris were as ineffectual as the French incursions into Alsace and the Rhineland. The war dragged on with both countries growing weary until at last a new peace was made. With no territories exchanged and photographs of devastated French land stretching for miles in the newspapers, much of Europe was disgusted by the seeming pointlessness of war. Germany even famously sat by, watching Russia attempt to meddle in Balkan affairs alongside the crumbling Austro-Hungarian Empire to the detriment of both.

In France, Napoleon IV received much of the blame despite his efforts to make the nation ready for invasion. Military historians note that without his improvements to infrastructure, the nation would have collapsed, but, at the time, Napoleon IV had to abdicate to save his house from being ejected from France. His cousin Victor became Napoleon V, causing trouble even among the Napoleonists who argued it should have been Victor's father or even his popular younger brother Louis. They were united, however, in that the Duke of Orleans should not come to the throne, as many called him the "Savior of France." Victor proved to be a good compromise overall, appealing to republicanists with his moderate politics and never backing down from the growing Orleans faction.

Germany, meanwhile, puzzled over the military struggling in a conflict that should have been won as quickly as the earlier Franco-Prussian War. It was agreed the issue was supply, so Wilhelm II's government invested heavily in Zeppelin's designs of airships, creating ones massive enough to carry industrial payloads. As the airships were easy targets for high-speed smaller aircraft, a generation of designers made improvements such as anti-aircraft defenses, internal lift-bags, and helium harvested from uranium mines. The demand for helium drove many of the schemes of Wilhelm III (then Prince Wilhelm and later "The Empire-Builder") to industrialize German colonies and build relations with the United States. Other designers focused on improving combat airplanes to serve as escorts, developing lighter, faster engines. Military advisers worldwide agreed the next war would be won by air superiority.