The National bank notes or currency of US was introduced under the Banking Act of the nation in 1863. This was primarily intended at making money for the federal government. The national bank notes had wonderful designs and are greatly collected. Because of their association with the local banks of US and because of these reasons, most of these national notes still exist.
National bank notes were suppressed in the year 1935. All that bonds intended to get bank notes was never continued after that. There was no direct backing up for national bank notes with the help of gold. This was hence considered not to be used for import duties or for public debt.