Post-traumatic stress disorder
Throughout history, there have been many accounts of people experiencing symptoms of what is now called PTSD. One such account describes Samuel Pepys, who witnessed the Great Fire of London in 1666. "Six months after the event, he wrote in his diary that he was unable to sleep at night, because a great fear of fire took him; one night he was unable to fall asleep before two in the morning, because of that fear."