The Plague of Justinian
Time: 541
Place: Mediterranean Basin
Details: The Plague of Justinian, considered the first recorded pandemic, breaks out and develops as an extended epidemic in the Mediterranean basin. According to some, frequent outbreaks over the next two hundred years would eventually kill an estimated 25 million people. This number has recently been disputed.
Best-effort ordering. Some events may appear out of order since many are only known to the year, but they are usually around the same period.