1908
Aldrich-Vreeland
Groups of national banks may issue emergency currency against more than government bonds. The same law funds a monetary commission. The Fed is 1913.

The Aldrich-Vreeland Act of 1908 let groups of national banks issue emergency currency against assets other than only government bonds. It was a response to the scramble of 1907.
The same law funded a National Monetary Commission. It did not create the Federal Reserve, and it did not redefine the dollar. The Federal Reserve Act is 1913.