April 9, 1859: A 23-year-old Missouri man named Samuel Langhorne Clemens (Mark Twain) receives his steamboat pilot's license.
For a starting point, here is my belief: Twain was a fantastic writer and a significant person in American history. As much as we would like to, we cannot erase the past--how we treated African-Americans, the harshness of the 19th century, etc. We can control how we teach these works. We can teach the brilliance of Twain's style, but point out the problems with the way he treated blacks, in conjunction with a little history of the period. We can also teach Twain's work alongside his contemporary, Harriet Beecher Stowe, whose famous anti-slavery novel Uncle Tom's Cabin contributed to the American Civil War.