Greenback (money)

Greenbacks were paper currency (printed in green on the back) issued by the United States during the American Civil War. They were in two forms: Demand Notes, issued in 1861–1862, and United States Notes issued in 1862–1865. They were legal tender by law, but were not backed by gold or silver, only the credibility of the U.S. government.

Before the Civil War, the only money issued by the United States was gold and silver coins, and only such coins ("specie") were legal tender; that is, payment in that form had to be accepted.

Paper currency in the form of banknotes was issued by privately owned banks; the notes being redeemable for specie at the bank's office. They were not legal tender. Such notes had value only if the bank could be counted on to redeem them. If a bank failed, its notes became worthless.

National governments had in the past issued paper money and made it legal tender, but usually with at least the pretense that the notes would be redeemable for specie at some time. Continental dollars issued by the Continental Congress during the American Revolution had no such backing, and soon became almost worthless.

During the early 1800s, the U.S. issued interest-bearing Treasury Notes in various denominations. These were not legal tender, but could be used to pay customs duties.

When President Abraham Lincoln assumed office, he understood the importance of money for the war effort. With this in mind, Lincoln appointed Salmon P. Chase as Secretary of the Treasury. As Secretary, Chase alone was authorized to act on all matters pertaining to the country’s finances. Chase, like almost everyone at the time, underestimated the duration and cost of the war. Within a few months it was clear that the costs of the war would run far beyond the government's limited income from tariffs and excises.

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