During the Civil War, both the North as well as the South developed their own currency. Ripped apart by war and teetering on bankruptcy, Congress ordered the printing of a number of notes. These Large Size Notes were commonly called horse blankets because of their dimensions. Issued from 1861 to 1928, their original size was approximately 7.42 inches by 3.13 inches. Cost cutting measures have reduced todays note to the more familiar 6.14 inches by 2.61 inches. Demand Notes or Greenbacks minted only in 1861 represent Americas first type of Federal Bank money.

United States Legal Tender (United States Notes) notes consisted of five issues:

• The first issue of March 10, 1862, was issued in denominations of $5, $10, $20, $50, $100, $500 and $1,000. There are two seperate obligationson the reverse side of these notes.
• The second issue, dated August 1, 1862, was confined to $1 and $2 notes, although the face design does indicate that a $3 denomination was planned, but not released.
• The third issue, dated March 10, 1863, was printed in the same denominations as the first issue, but changes were made to the back design.
• The fourth issue was printed under authority of the Congressional Act of March 3rd, 1863. These notes were issued from $1 to $10,000 denominations and included the of Series 1869, 1874, 1878, 1880, 1907, 1917 and 1923, with all except the 1869 notes carrying the designation "United States Note." The 1869 series was designated as "Treasury Note." The United States introduced paper with silk threads as a deterrent to counterfeiting with the Series 1869 notes.
• The fifth issue was limited to the $10 denomination series of 1901. (The Bison Note). These notes were issued under the authority of the Legal Tender Acts of 1862 and 1863.