Tax Day 2011: When did America levy its first income tax? The Civil War.

The Civil War, which began on the twelfth of April 150 years ago, transformed America financially as it did in so many other ways.

Abraham Lincoln instituted America's first income tax in 1862, as he searched for money that would enable the union to wage and win the war. Along with this move came tax-code complexity and a new agency called the Bureau of Internal Revenue.

Some 150 years later, things have changed ... and things have stayed the same.

Since the Civil War, the income tax has been declared unconstitutional, then legalized by an amendment to the US Constitution, then expanded, then greatly reduced.

But after 150 years, Americans still owe income taxes – due April 18 this year. They still struggle with arcane tax rules. And they still worry about the far-reaching tentacles of the agency now known as the Internal Revenue Service.

"The Civil War income tax was the first tax paid on individual incomes by residents of the United States," wrote Cynthia G. Fox, chief of the Military and Civil Records Unit of the National Archives. An article she wrote for an Archives publication recounted the gory details – not of the war, but of how it was financed:

• Taxes were levied on residents of "all states and territories not in rebellion," including areas of the South after Union troops established control. People in northern and western Virginia were subject to the income tax from its very start. Georgians paid the tax in 1865, even though Georgia was not readmitted to the Union until 1870.

• The tax was progressive: the initial rate was 3 percent of incomes over $600, and 5 percent on any income over $10,000. In 1864, the rate bumped up to 5 percent on incomes above $600 and 10 percent on incomes above $5,000.

• The tax provided for deductions, such as for a farmer's cost of livestock, insurance, and interest. Businesses could deduct expenses including rent, freight, and wages.

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• The income tax was part of a large and complicated web of federal levies during the war, ranging from duties on specific industries (transportation) and products (zinc) to license fees for a host of occupations.

According to histories kept by the Library of Congress and the US Treasury, Congress's Revenue Act of 1861 included a tax on personal income. But the first income tax collections began after the Revenue Act of 1862, which established the commissioner of Internal Revenue. "The income tax generated approximately $55 million in government revenues during the war," wrote Fox.

The tax was repealed in 1872.

In 1895, the US Supreme Court ruled that a new income tax (passed in 1894) was unconstitutional, because it was a direct tax on individuals and not apportioned among the states on the basis of population. In 1913, the sixteenth amendment to the Constitution was ratified, paving the way for income taxes in the modern era. The first Form 1040 was introduced in that year.

The top-bracket tax rate reached a high of 94 percent during World War II, according to data from CCH, a provider of tax information. Since then, the top rate has fallen gradually, reaching 50 percent in 1982 and 35 percent today.

Tax Day 2011:

Part 1: When is the tax deadline? Hint: It's not April 15.

Part 2: What's new for homeowners?

Part 3: Checking on your refund? There's an IRS app for that.

Part 4: When did America levy its first income tax? The Civil War.

Part 5: Schedule M could be worth up to $800

Part 6: Four ways to protect your tax returns from data thieves

Part 7: Last-minute tips to keep the Internal Revenue Service away

Part 8: Tax Day 2011: Why do presidents release tax returns? Hint: 'I am not a ...'

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