In 1483, the sudden death of King Edward IV left the throne of England in the hands of his 12 year old son. Edward IV's son, Edward V, and his brother were taken into custody by their uncle at the Tower of London, and disappeared shortly after. Although there has been much speculation as to what happened to them over the years, no one truly knows the fate of the two princes.
The two princes were murdered
Many stood to gain from the deaths of the two young princes, and the list of suspects is limitless. That being said, there are a few notable suspects with proper means, motive, and opportunity.
The two princes were murdered by their uncle Richard III
The most commonly accepted theory is that Richard III murdered his two nephews in order to take control of the throne.
The princes' and their family understood the danger that the sudden death of Edward IV placed them in. Faced with the choice of either staying in power and living in fear, or fleeing for safety, the princes' could have either run away, or been hidden by their family.
The Princes' family hid them for protection
Many people would have profited from the death of the two princes. This is exactly why their family would have hidden them until they were old enough to fend for themselves.