At the country's Founding, income tax was zero percent. The government, in times of peace, was funded on tariffs from imported goods. Needless to say, the Founders and Americans were not fond of taxes in general. In fact, the Supreme Court ruled income tax unconstitutional in 1895. So what changed that made income tax permanent and rates dramatically fluctuate?
Here's a visual walk down memory lane from the Founding of the United States in 1787 to the current income tax rates.
CHALLENGE: Test your knowledge first by taking our History of Income Tax Quiz.

NOTE: Tax rates shown are the highest possible rates on individual taxpayers. With few exceptions, a graduated income tax has been imposed whenever income tax existed.
SOURCES:Tax Foundation, IRS, Forbes