sentences:  The first federally-issued paper currency was circulated by the US Treasury Department following the outbreak of the Civil War.Congress passed authorizing legislation for $60 million worth of these "Demand Notes" on July 17 and August 5, 1861.Under contract with the government, the novel paper money, called "greenbacks" by the public, was produced by the American Bank Note Co. and the National Bank Note Co. A total of 7.25 million notes were produced in denominations of $5, $10, and $20.