Who issued the country's early currency and what was the principle problem that occurred?

Benjamin Franklin

Early American currency went through several stages of development during the colonial and post-Revolutionary history of the United States. Because few coins were minted in the thirteen colonies that became the United States, foreign coins like the Spanish dollar were widely circulated. Colonial governments sometimes issued paper money to facilitate economic activities. The British Parliament passed Currency Acts in 1751, 1764, and 1773 that regulated colonial paper money.

During the American Revolution, the colonies became independent states. Freed from British monetary regulations, they issued paper money to pay for military expenses. The Continental Congress also issued paper money during the Revolution, known as Continental currency, to fund the war effort. Both state and Continental currency depreciated rapidly, becoming practically worthless by the end of the war. This depreciation was caused by the government printing large amounts of currency in order to meet the demands of war.

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use wikipedia, i think they have this.