Since 1914 Tax Day has been an annual occurrence. The first “Tax Day” occurred shortly after the passing of the 16th Amendment, which was about one year before thus why it originally fell on March 1st. Four years later it was switched to March 16th, and then April 15, 1955. The reason it was pushed back was to ease the workload of IRS workers, but some believe it is to delay tax refunds as long as possible. This year tax day is April 18th.
Why does the government receive “Income Tax”? During the Civil War, income revenue was used to help fund the war (this is due to the Revenue Act of 1861). This act was challenged as unconstitutional in the Pollock v. Farmers’ Loan & Trust Co. Eventually in 1913, the 16th Amendment was ratified. This allows the US Congress to legally tax all incomes. Good for the government but bad for us lowly tax payers!