Complex sentence: September was the birth month of no fewer than four major Roman emperors, including Augustus, and the emperor Commodus renamed the month either after himself or Hercules--an innovation that was repealed after his murder in 192.
Split into simpler sentences: September was the birth month of no fewer than four major Roman emperors, including Augustus. The emperor Commodus renamed the month after either himself or Hercules--an innovation that was repealed after his murder in 192.