Emancipation Day is April 16th this year, and April 15th is a Sunday, so the filing season is extended again for 2011 returns until April 17th. Extensions are still good until October 15th, you don’t get an extra two days on the extension deadline.
April 16th was the day Abraham Lincoln signed the Compensated Emancipation Act in 1862 for the release from slavery of people held in the District of Columbia. This was nine months before the Emancipation Proclamation, the one you’ve heard of before, was signed on January 1, 1863—and for tax purposes, this one was already a holiday. Because the Mayor of DC declared this day a public holiday, it has affected Federal tax filing deadlines.
The Emancipation Proclamation provided freedom for slaves in states that did not return to the Union, but didn’t outlaw slavery. That wasn’t until the Thirteenth Amendment took effect in December 1865.
When I was in St Louis at an NATP conference last year, I had a few hours before I had to be at the airport, so I got a cup of coffee and wandered around the neighborhood next to the St Louis Arch. I went into the old courthouse building behind the hotel, and discovered an exhibit about the Dred Scott case, which had been decided there in the 1850s. And I was reading Team of Rivals by Doris Kearns Goodwin at the time, which I’ll recommend. The book includes some of the same images they have in their display at the courthouse.