Coriolanus said:
Grey Wolf, could you tell us more about a ten year Crimean War, and the plan the UK and France had to extend the war?
1856 was to see a major offensive in the Baltic, the involvement of Sweden who had now signed a definite alliance with the offensive powers. Britain had built a massive fleet of narrow-draught gunboats etc. The idea was to invade Finland and destroy Kronstadt
The problem was that this was to be in association with another front - and that is what the British and French could not agree on. Britain, with her focus on destroying Russia's threat in Central Asia wanted the new front to be in Circassia (Caucasus) whereas Napoleon III dreamt of a revived and independent Poland.
This idea of Poland might be seen as a threat to Austria, but in this period I don't think so. In 1862 when the Polish revolution broke out, the hope in Vienna was that an Austrian Archduke would assume the throne of an independent Poland, and effect a union of the Russian part of Galicia in close alliance to Austria. Maximilian (of Mexico fame) was to have been offered such a throne. But in 1862 Russia crushed the revolutionaries.
Thus, in order to continue OTL's Crimean War into 1856 you need to find a compromise between Britain and France to continue the war. Once you have done that, you can begin to look at other effects
By 1856 Britain and the USA had broken off diplomatic relations, the USA was close to the Russian Empire and it is expected that if the war continues the USA will enter. Its not as much a losing proposition as it seems - the USA's war will largely be against Britain.
In addition, the ultimatum from Austria which brought an end to the Crimean War was directed against Russia. Russia's acceptance met with British and French disagreement. If Austria had not been aware of this latter effect, it is unlikely they would have made the ultimatum to Saint Petersburg - i.e. if Russian acceptance would not have been acceptable to Britain and France, then Austria would not have sent the ultimatum. Instead, Austria would have found itself bound to Britain and France in its alliance, and as 1856 opened it would have had to enter the war.
Grey Wolf