Lincoln signed the first income tax law. August 5, 1861 – The federal government levied an income tax for the first time; President Lincoln signed the Revenue Act to raise cash to pursue the Civil War; Lincoln and Congress agreed to impose a 3 percent tax on annual incomes over $800. Act broadly written, defined income as gain “derived from any kind of property, or from any professional trade, employment, or vocation carried on in the United States or elsewhere or from any source whatever. SOURCE
1861 First U.S. income tax: Pres. Lincoln signs into law a 3% tax on incomes over $800, effective January 1, 1861. It was rescinded in 1872. SOURCE
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