The simple facts are difficult to argue. I can eat small pieces of gold though. I just have never done it.
So I may be getting your point incorrect.
I have spent a little time and believe that fiat began in America post-Constitution in around 1815 - the War of 1812 Era it is called. So I still believe it is Emergency-based but have proposed for a while that it was 1861, that Emergency. I was trying to find somebody who could show me differently with that assertion and finally got some better information.
The American Numismatic Association - the exhibits are - Money of the Civil War and The History of Money.