1 of 6 | Marchers in the Million Mom March start out walking down the National Mall with the Washington Monument in the background on May 14, 2000. File Photo by Joel Rennich/UPI | License Photo On this date in history: In 1643, King Louis XIV, who would be known as "The Sun King," became ruler of France at the age of 4. In 1796, Dr. Edward Jenner, a rural England physician, tested his smallpox vaccine. It was a success. In 1804, one year after the United States doubled its territory with the Louisiana Purchase, the Lewis and Clark expedition...