The reason paper money finally took hold was primarily because the National Banking Act of 1863 established a national banking system, with a uniform currency. This required banks to purchase U.S. government securi-ties as backing for their bank notes. The first $1 bill was issued in 1862 as a Legal Tender Note with the portrait of Salmon P. Chase on it. Chase was the Treasury Secretary under President Abraham Lincoln.
Gold certificates were first issued in 1863 and silver certificates in 1878. The Great Depression saw the end of gold certificates, but the silver certifi-cates lasted until the early 1960's, when rising silver prices threatened to un-dermine the currency system.
Though the current US dollar design technically dates to 1963, many of the design elements were introduced in 1929. New designs for all denomina-tions of US bills have been under discussion for many years now.