The incident

A depiction of the eruption which buried Pompeii (from BBC's Pompeii: The Last Day). The depiction of the Temple of Jupiter and the Temple of Apollo are nonetheless inaccurate as these temples had been destroyed 17 years earlier.

By the 1st century, Pompeii was one of a number of towns located around the base of Mount Vesuvius. The area had a substantial population which grew prosperous from the region's renowned agricultural fertility. Many of Pompeii's neighboring communities, most famously Herculaneum, also suffered damage or destruction during the 79 eruption. By coincidence it was the day after Vulcanalia, the festival of the Roman god of fire.

The people and buildings of Pompeii were covered in up to twelve different layers of soil. Pliny the Younger provides a first-hand account of the eruption of Mount Vesuvius from his position across the Bay of Naples at Misenum, in a version which was written 25 years after the event. The experience must have been etched on his memory given the trauma of the occasion, and the loss of his uncle, Pliny the Elder, with whom he had a close relationship. His uncle lost his life while attempting to rescue stranded victims. As Admiral of the fleet, he had ordered the ships of the Imperial Navy stationed at Misenum to cross the bay to assist evacuation attempts. Volcanologists have recognised the importance of Pliny the Younger's account of the eruption by calling similar events "Plinian".
The eruption was documented by contemporary historians and is universally accepted as having started on 24 August 79, based on one version of Pliny's letter. However the archeological excavations of Pompeii suggest that it was buried 2 months later; this is supported by another version of the letter. People buried in the ash appear to be wearing warmer clothing than the light summer clothes that would be expected in August. The fresh fruit and vegetables in the shops are typical of October, and conversely the summer fruit that would have been typical of August was already being sold in dried, or conserved form. Wine fermenting jars had been sealed over, and this would have happened around the end of October. The coins found in the purse of a woman buried in the ash include a commemorative coin that should have been minted at the end of September. So far there is no definitive theory as to why there should be such an apparent discrepancy.