Year 430 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Crassus and Iullus (or, less frequently, year 324 Ab urbe condita). The denomination 430 BC for this year has been used since the early medieval period, when the Anno Dominicalendar era became the prevalent method in Europe for naming years.
The army of Sparta loots Attica for a second time, but Pericles is not daunted and refuses to revise his initial strategy. Unwilling to engage the Spartan army in battle, he again leads a naval expedition to plunder the coasts of the Peloponnesus, this time taking 100 Athenian ships with him.
An outbreak of a plague hits Athens and the disease ravages the densely packed city (modern DNA analyses of material from ancient cemeteries suggest the mortal disease may have been typhus). The plague wipes out over 30,000 citizens, sailors and soldiers as well as Pericles' two sons. Roughly one quarter of the Athenian population dies. The fear of plague is so widespread that the Spartan invasion of Attica is abandoned, their troops being unwilling to risk contact with the diseased enemy.
Pericles becomes ill from the plague but he recovers, temporarily. He is deposed from his position as General (or Strategos), but is later reappointed.