They were sold to the public with the idea that a personal income tax would never affect the working man, just THE RICH ~ in fact, just the top 1% or maybe 2% of folks with cash income.
Don't blame it on Wilson!
The post was about 1913. I just Googled who was president at the time. It was a Democrat. Okay???
Republican and Democrat means two different things today. For example, Grover Cleveland-a Democrat-would be considered a Conservative today.
That was the 61st Congress. Go here for details about the 61st.
The "Progressive Era" occurred from about the 1890's up to about the end of WWI. Prominent Democrats and Republicans of the period were Progressives, so legislation enacted during that time can't be laid solely at the feet of either the Democrats or Republicans. Theodore Roosevelt, William Jennings Bryan, Louis Brandeis, Samuel Gompers, and Susan B. Anthony are a few examples of early Progressives.
Also, we can't lose sight of the fact that the 16th and 17th Amendments were both ratified by the states, and that took majority votes of 48 state legislatures.
The early Progressive Era focused mostly on social and business reforms. That era really can't be compared directly with modern progressives, since over the past 100 years, progressives have increasingly moved to the far Left politically.
The first income tax was enacted to raise revenue to fund the Civil War, when Congress passed the Revenue Act of 1861. It levied a flat tax of 3% on annual income above $800.
Then, 26 years later, the Socialist Labor Party advocated a graduated income tax in 1887. The Populist Party also "demanded" a graduated income tax in its 1892 platform. The Democratic Party, led by William Jennings Bryan, joined in and advocated the income tax law passed in 1894, and proposed an income tax in its 1908 platform.