Today in 1861, President Lincoln imposed the first income tax in order to pay for the Civil War. This first tax levied a 3% tax on all incomes over $800.00. Congress repealed Lincoln’s tax law in 1871, but in 1909 passed the 16th Amendment, which set in place the federal income-tax system used today. Congress ratified the 16th Amendment in 1913.
The Law Library has some outstanding resources on the history of Federal Income Tax, including Hein’s Taxation and Economic Reform Part 1 & 2 (and Part 3), Making the Modern American Fiscal State: Law, Politics, and the Rise of Progressive Taxation, 1877-1929, and Seidman’s Legislative History of Federal Income Tax Laws. Please see a reference librarian if you would like to see more resources on this topic!