A Franco-Austrian Alliance

I doubt that France could intervene successfully. The problems which appeared during the mobilization and the concentration of the French Army in july 1870 would also happen in 1866, and the French would even be in a worst shape than in 1870 as the reforms of Niel haven't even been launched. By the time, the French would put a foot into Rhineland, Hanover would have been for long defeated and occupied by the Prussians.
What's more, the mobilization that Napoleon III was about to order IOTL was to bring Prussia to peace negociations, not to commit France into a war.
Unless you prevent the defeat of Sadowa, all you can do is making the treaty of Prague less harsh for Austria.
Since Luxembourg was the price of the French neutrality, I imagine that by mobilizing, Napoleon III could forget it.

Preventing a united Germany to appear at the border would continue to be the main priority of both French and Austrian foreign policies, what makes an alliance necessary.

Past Napoleon III, French colonial expansion would lead to clash with the UK (Egypt, Indochina...) and would exacerbate French anglophobia (remember the Fashoda crisis). With the Great Game underway in Central Asia, it seems logical that France would support Russia against the UK. In turn, this would lead the Ottomans to seek protection of the British against Russian expansionism in Caucasus and Balkans.

Although Italy should continue to be aligned with France (the Italians asked for the approval of Napoleon III before accepting an alliance with Prussia in 1866), if the problem of Rome isn't quickly solved, this could push Italy in an alliance with the British.
 
Why does everyone assume Hanover was curb-stomped by the Prussians?! In fact the Hanoverian Army DEFEATED the Prussians at Landfelt (not sure of the spelling). It was a hell of a bloody victory for the Hanoverians but it was a sufficient victory to buy enough time for some Franch reinforcement to arrive.

Nonetheless the Austrians do need to perform better at Sadowa for any of this to be relevant...
 

Razgriz 2K9

Banned
While it is true that Hannover did score a victory over Prussia in that battle, Prussian troops still outnumbered Hannovers even with much of their army in Bohemia and Saxony thanks to their reserve force, which was actually made in order to prevent France from outflanking them.

And what reforms are you talking about Gallileo? I remember seeing that the French Army of 1866 was better by leaps and bounds than the French Army that fought Prussia OTL in 1870, even if it probably wasn't as good as say the French Army of the early 19th century or before.
 
Top