George Washington's teeth were not made of wood. His dentures were made of gold, hippopotamus ivory, lead, and human teeth, horse teeth, and donkey teeth. More info on NBC News.
Columbus not only didn't discover what became the mainland U.S (natives got there long before), but Columbus never even it. The closest he got was the Carribean Islands. More info on Wikipedia.
Vikings never wore horns on their helmets. The popular image of Vikings with horned helmets originated from an opera by Richard Wagner in 1876. More info on Scribd.
Napoleon Bonaparte was not short. He was 5'7'', which was slightly taller than the average Frenchman of the time (early 1800s). He selected his imperial guards based on their height, which may have contributed to the perception that he is short. More info on About.com.
The rumor is false that today's popular image of Santa Claus was created by Coca-Cola. The current iteration of Santa Claus had already been popularized by multiple other companies before Coca-Cola adopted the image. More info on Snopes.
Iron Maidens were not invented in the Medieval period (5th-15th centuries) or ever used for torture. Iron Maidens were invented in the 18th century and pieced together from artifacts in museums in order to increase museum earnings. More info on Wikipedia.
The rumor that Albert Einstein failed math in school is a false claim published by Ripley's. When Einstein saw it, he said, "I never failed in mathematics... Before I was fifteen I had mastered differential and integral calculus." More info on Time.
Medieval Europeans did not believe the earth was flat. From the time of ancient Greek philosophers like Plato and Aristotle, nearly all European intellectuals accepted the spherical earth theory. Columbus had trouble finding support because peers correctly believed his target of the East Indies was further than he thought. More info in Terra Cognita.
Benjamin Franklin did not propose the wild turkey as the symbol for the United States instead of the bald eagle. He once wrote a private letter to his daughter expressing his dislike of the eagle and preference for the turkey, but never expressed that sentiment publicly. More info on Slate.
Chastity belts were not invented in the Middle Ages (5th-15th centuries) to prevent women from losing their virginity. They were invented in the 18th century to prevent teenagers from masturbating because they thought masturbation led to insanity. More info on Wikipedia.
Marie Antoinette did not say "Let them eat cake" when she found out the French peasantry was starving. The quote was published by Rousseau when she was 10 years old and was more likely said by the king's wife or made up by Rousseau. Antoinette later became an unpopular ruler, so the peasantry was happy to attribute the quote to her. More info on HowStuffWorks.com.
Cinco de Mayo is not Mexico's Independence Day. Mexico's Independence from Spain is celebrated on September 16. Cinco de Mayo celebrates Mexico's victory against the French in the Battle of Puebla. More info on Discovery.
Vomitoriums were not used for vomiting, and it was not customary to vomit between courses while dining in ancient Rome. Vomitoriums were the entrances through which Roman crowds entered and exited stadiums. More info in A Cabinet of Roman Curiositie.
Nobody was burned at the stake during the Salem witch trials. The accused either died in prison or were hanged. More info in The Specter of Salem.
The Pilgrims did not have buckles on their hats or wear the same, dark colored clothing. The popularized image of pilgrims was created in the 19th century (3 centuries later) when buckles were a symbol of quaintness. More info on Wikipedia.
The U.S Declaration of Independence was not signed on July 4, 1776. It was approved by Congress on that date and signed on August 2, 1776. More info on Archives.gov.