Dear Armand
The finances of France were ruined by the Seven Years War, famine, support of American Independence, Revolutionary wars, Napoleonic Wars, Continental Blockade etc
.
The only way that France could balance the books was to plunder the riches off other countries. This worked to 1807 but soon started to unravel. The expence of the standing army fell upon the Confederation of the Rhine, Duchy of Warsaw, Italy, Naples and Prussia. The expense of the army in Spain was initially carried by Spain but soon this poor country could not maintain them.
Napoleon should have stopped in 1807 with what he had and consolidated but was probably driven by the financial issues. The beleif that he could defeat the British by the continental blockade was ruinous. This lead him to annex Hanover, northern Westphalia and Oldenburg. The last was an offront to the Tsar who was related to the Oldenburg family.
The offer of peace at the various times in 1813 was very generous. It could be that he could not have accepted these as this would admit defeat and so undermine his power in France. The other explanation is less flattering of course. A conqueror does not know when to stop.
The decision he made strategically after 1807 were in the main political rather than military. These were often poor. He army had grown to huge proportions so could not be controlled and the timing/opportunity in battles lost. The system of communication he required was only solved in part in the First World War with field telephones etc
and in the 1930s with increased use of radio communication.
Austria was playing like the other combatants a careful game. It was not really a winner out of the Congress of Vienna. It had lost leadership in Germany and had not regained it. It regained the Tyrol and Italy. A strong France was essential to Austria. It was how to acheive this. Austria had become denuded of money through war in 1793-6, 1799-1800, 1805, 1809, 1812, 1813-4 and finally 1815. Her richer areas had been removed from her and lost a seaport to the outside world.
You could say money makes the world go around. Alas Central Europe there was no cash flow. It was in the position as we now have of the credit crunch. Currencies were devalued and too much paper promisary notes from the French occupation forces/garrisons etc
The economy and industry was ruined.
Stephen