Very interesting. Suppose that N. really wanted peace, and the entire Vienna Congress suddenly decided that, (notwithstanding the fact that they had just spent the last 17 years or so trying to destroy him!) they would accede. Peace puts Napoleon in a very difficult position. Im not too sure of Frances financial position during the return(?), but Im assuming N. couldnt afford to maintain the army. First of all this would deprive him somewhat of his main and most influential supporters,
unpopularity with the army would have been extremely unhealthy.
He would also have lost the popularity and, consequentially, the support of, many of the lower peasantry or rural proletariat. These profited from the shortage of farm hands following conscription, their wages rose 20% between 1798 and 1815. No war meant no conscription which meant a
loss in scarcity value.
And the moneyed Úlite, would soon lose interest in Napoleon. To them,
armies and war offered entrepreneurial oppurtunites, ie. military supplies, colonial produce, speculation in national property etc.
I dont think peace would actually toppled Napoleon in 1815, (or would it?) but it certainly would have deprived him of much of his traditional support base.
War was, I believe, in any case inevitable. Even if peace had been
negotiated in 1815 (extremely unlikely!) Napoleon needed a war to assure the army, the generals, and the French that he hadnt lost his genius. No doubt the treasury could have done with the resultant spoils too.