A Voyage into Catastrophe: Pompeii and the Roman Navy

Article | Updated 1 month ago

By Will Mather

Caption: The Roman navy approaches the base of Mount Vesuvius.
Image Escape from Pompeii: the untold Roman Rescue

Collecting material for a history of the Roman Empire, the historian Tacitus sent a letter to Pliny the Younger asking for an account of the death of his famous uncle, the polymath Pliny the Elder, who had died some 25 years earlier in 79 AD. Pliny’s gripping reply is the only eyewitness account of the eruption of Mount Vesuvius, which devastated Campania, burying the towns of Pompeii, Herculaneum and Stabiae. It is also the only account of Pliny the Elder’s attempted rescue of civilians from the disaster using the ships of the Roman navy – an effort that cost him his life.

An unlikely hero, Pliny was 55, overweight, asthmatic and a bookworm with a long list of published works to his name. His most famous work, his Natural History, still survives today. Published just before the eruption, it covers a huge range of natural history topics – astronomy, geography, zoology, botany, agriculture, medicinal drugs obtained from nature, mining and minerals – in 37 books. As he writes in his preface, the Natural History contains more than 20,000 facts mined from 100 authors, which he hoped would be a useful reference work for the masses, farmers and artisans. It is one of the few works to survive from antiquity, as it did indeed prove useful.

Pliny was born in Como in northern Italy at the foot of the Alps, a region that had only fairly recently been given Roman citizenship. In his discussion on wool Pliny recounts that his father remembered wearing rough woollen topcoats, while he recalled coats shaggy inside and out, as well as shaggy woollen waist bands – clearly, they were not toga wearers. His family belonged to the equestrian class, just beneath the senatorial class in wealth and status. Pliny did his military service in the cavalry on the German frontier. There he served with Titus, who would follow his father Vespasian to become emperor after the overthrow of the emperor Nero. Pliny did not seek any office under the flamboyant but murderous Nero. Only with the accession of Vespasian in 69 AD did Pliny take up public office, serving the new emperor as procurator in Roman provinces in France, Spain and North Africa. A procurator was a kind of chief financial officer of the province, there to assist the governor in financial matters but also to keep an eye on him for the emperor. When in Rome, Pliny served on Vespasian’s private advisory council, confirming he was in the inner circle of the new regime.

Pliny was responsible for the whole of the western Mediterranean and, most importantly, Rome

Around 76 AD he was appointed commander of the Roman naval base at Misenum on the Bay of Naples. This was the highest-paid and highest-ranking position outside Rome. The fleet had about 50 warships and 10,000 men, and was the largest military force in Italy, the legions being far away on the empire’s borders. Pliny was responsible for the whole of the western Mediterranean and, most importantly, Rome. In the absence of any enemies the fleet’s role was to suppress piracy and provide speedy communications throughout the empire.

Misenum was some 250 kilometres from Rome – not particularly close, but the Bay of Naples provided the best harbours along the entire west coast of Italy. Rome’s port at Ostia, at the mouth of the Tiber, was too exposed to storms and flooding to be used as a naval base, nor was it a good commercial port; 200 grain ships were destroyed in one storm there in 62 AD. With its two flooded volcanic craters Misenum proved ideal, providing an inner and outer harbour protected from winds and with beaches for careening ships. It could protect Rome’s main commercial port further along the Bay at Puteoli (Pozzuoli). The famous grain fleet from Egypt that fed Rome docked there, as the ships were too large for Ostia.

Herculaneum, favoured for its sea breezes, was more of a resort, while Pompeii with its river port was more commercial

Puteoli was also the hub for luxury goods coming from the east, highly convenient for the Roman elite who chose the Bay of Naples as their favoured holiday destination, attracted by its beauty and climate. The volcanic action that made the great harbours also made the volcanic springs. The spa resort of Baiae, next door to Misenum, was particularly popular. Nowhere had more plentiful or more healing water, according to Pliny. Food was another attraction – the fish and shellfish were unequalled, and the volcanic soils made the area the most fertile in Italy.

Next comes the well-known fertile region of Campania. In its hollows begin the vine bearing hills and the celebrated effects of the juice of the vine, famous the world over, and, as writers have said, the venue of the greatest competition between Bacchus and Ceres … These shores are watered by hot springs and in no seas can the repute of their famous fish and shellfish be equalled. Nowhere is the olive-oil superior, another object of mankind’s pleasure.  – Pliny the Elder, Natural History III 60


Across the bay, beneath Mount Vesuvius, Pompeii and Herculaneum tapped into this network. Herculaneum, favoured for its sea breezes, was more of a resort, while Pompeii with its river port – which also served three towns further inland – was more commercial. Both were wealthy and connected to the capital and to the wider Mediterranean world due to their position on the bay and, thanks to Vesuvius, the fertility of their lands.

Pliny had no wife or children of his own, and at Misenum his widowed sister and her teenage son, Pliny the Younger, lived with him. Around 1 pm on 24 August 79 AD, his sister drew his attention to a cloud of unusual shape and size, resembling an umbrella pine, rising from a mountain in the distance (later ascertained to be Vesuvius). Pliny’s interest piqued by what he thought was a relatively benign natural phenomenon, he ordered a Liburnian galley – one of the small, fast ships originally used by the pirates of Dalmatia – to be made ready to go and have a closer look.

He then received a message from his friend Rectina begging to be rescued. Her villa was at the foot of the mountain and the only escape was by sea (how she got the message to Pliny is not explained). Realising that people’s lives were in danger, he ordered out the warships to save as many people as possible.

He changed his plans, and what he had begun in a spirit of inquiry he completed as a hero. He gave orders for the warships to be launched and went on board himself with the intention of bringing help to many more people besides Rectina, for this lovely stretch of coast was thickly populated.  – Pliny the Younger, Letters VI 16

The warships Pliny sent out were quadriremes, the largest ships in his fleet at 39 metres long and four metres wide. Each was powered by 232 oarsmen arranged in four banks called remes (hence the name of the ship). Attached to the bow of each vessel was a large metal beak called a rostrum, designed for ramming enemy ships to sink or disable them, the oarsmen providing the power. Oar power also made the ships highly manoeuvrable, ideal for the tricky situation into which they were going. Sails were used to get the ships to and from battle sites, and were most likely used to get the ships across the bay. The wind blowing from the north-west was in their favour.


Vesuvius was 28 kilometres away, and with an estimated speed of eight knots it would have taken the ships around three-and-a-half hours to get there. On the way Pliny was dictating, taking notes on each new movement and phase of the eruption. Hot ash started falling thickly on the ships, followed by pumice, around 5 pm as they neared the coast. Suddenly the water became shallow, caused by the seabed rising as Vesuvius’ magma chamber filled, and they were prevented from getting any closer to the shore by rafts of pumice.

Ashes were already falling, hotter and thicker as the ships drew near, followed by bits of pumice and blackened stones, charred and cracked by the flames: then suddenly they were in shallow water, and the shore was blocked by the debris from the mountain. – Pliny the Younger, Letters VI 16

Caption: Mount Vesuvius from Sorrento.
Image courtesy Matthew O'Sullivan

This indicates that they attempted to land somewhere south of Herculaneum, as that town had virtually no pumice fall during the entire eruption. This was due to the prevailing north-west wind blowing the ash and pumice south-east over Pompeii, where it had been falling since midday at a rate of about 15 centimetres an hour. As Pliny approached the coast, balconies and roofs in Pompeii were beginning to collapse from the weight. It would have been increasingly dangerous to stay indoors. Though there was little ash fall at Herculaneum, the ominous 30-kilometre-high volcanic cloud would have cast the town into darkness and the constant tremors would have encouraged people to flee or seek shelter in stronger buildings, like the arched superstructure of the Suburban Baths where most of Herculaneum’s victims were found.

The decision to run or stay during this period was fateful

Pliny refused to retreat. He ordered his ship south past Pompeii to Stabiae, to the villa of his friend Pomponianus. On arrival he found Pomponianus wisely trying to leave, having loaded his belongings onto a ship, although he was unable to depart due to the contrary wind. Pliny had made a miscalculation; having landed, he too was unable to leave for the same reason. He stayed in his friend’s villa. During the night more pumice fell, the level rising so high there was danger of Pliny being stuck inside his bedroom. He joined the others and they debated whether to stay indoors or take their chance in the open, as the buildings were now shaking violently. It was a debate that would have been happening throughout Pompeii as well. Choosing to stay outdoors, they tied pillows to their heads to protect themselves from falling debris.

The decision to run or stay during this period was fateful. The deadly phase of the eruption was about to begin as the volcanic cloud began collapsing. Around 1 am the first pyroclastic surge of superheated gas and ash travelling at 30 metres per second smashed into Herculaneum, instantly killing everyone still there. At 400–450 degrees Celsius it carbonised wood, leather and foodstuffs and burned the flesh off living people. Further flows buried the town and extended the coastline 400 metres to the west.

The first surge and the next two did not reach Pompeii. When the fourth surge swept over Pompeii just after dawn, at 6.30 am, it killed everyone still present. Many were found trying to make their escape over the pumice fall. This surge was not as hot – it did not burn the bodies but rather formed a hard shell around them, creating a void once the bodies decomposed. It is from these voids that the famous Pompeiian body casts were made. Before the pyroclastic flow, deaths in Pompeii would have been from building collapse, and these bodies did not form casts as they were buried in loose pumice and ash.

Caption: Body cast of one of the victims from Pompeii. This is a copy of a cast made in 1875. It shows the victim with her clothes forced up around her waist from the power of the pyroclastic surge.
Image copyright Ministero dei beni e delle attività culturali e del turismo – Soprintendenza Speciale Pompei

The fourth surge, or the ones that came quickly after it, caused panic in Stabiae, 14 kilometres from the crater. Flames and the smell of sulphur gave warning of the approaching surge. Pliny tried to flee with the others, but the fumes and ash caused too much stress on his lungs and heart and he collapsed and died. His body was found two days later. Due to Stabiae’s distance from Vesuvius, and possibly the intervening Sarno river, the surge that reached Stabiae had cooled, so wasn’t fatal to all those present.

To date, 1,500 bodies have been found at Pompeii, and 350 at Herculaneum – about 10 per cent of their estimated populations

Whether or not the ships sent out by Pliny the Elder saved anyone is not clear from his nephew’s account, but then its main focus was not the rescue but his uncle, of whom he was genuinely fond. Pliny the Younger does make it clear that people were leaving the area as his uncle went in, and people in both towns had plenty of time to leave – in Pompeii’s case 18 hours – though this would have been increasingly difficult with the constant rain and build-up of pumice, and the complete darkness. To date, 1,500 bodies have been found at Pompeii, and 350 at Herculaneum – only about 10 per cent of their estimated populations. More victims may be found along the roads leading out of the towns or in their still-undiscovered ports, but it is likely most people escaped.

The ash cloud was so great it darkened Rome, and some of the ash reached Africa, Syria and Egypt. The emperor Titus, Pliny’s patron, appointed a board of magistrates to relieve the distress in Campania and he went there himself to supervise the disaster relief first hand.

Pliny the Elder does not seem to have been aware that Vesuvius was a volcano, though he mentions the ones in the nearby Aeolian Islands and Mount Etna in Sicily. Earlier authors did think it had been an active volcano from the scorching found on its summit, but it had been dormant for a very long time. The link between volcanic eruptions and earthquakes was also not yet understood. Pliny held the common view that they were caused by wind:

I think there is no doubt that winds cause earthquakes. For earth tremors never occur unless the sea is calm and the sky so motionless that birds cannot hover,because all the air which bears them up has been taken away. – Pliny the Elder, Natural History II 192

A devastating earthquake in 63 AD that destroyed parts of Herculaneum and Pompeii was most likely caused by magma rising beneath Vesuvius. Another major earthquake in 64 AD destroyed the theatre at Naples. Although many fled the area after the 63 AD earthquake, tremors had become so common just prior to the eruption that they ceased to cause alarm.

In his will Pliny left his entire estate to his nephew, and also adopted him. His nephew then took his name to become Pliny the Younger. He went on to have a successful political and literary career, hence the survival of his letters to Tacitus. The section of Tacitus’ Histories in which he described the eruption of Mount Vesuvius has not survived. It would have been very interesting to see how closely he followed Pliny the Younger’s account and in what light he put Pliny’s uncle – whether heroic or foolhardy.

Escape from Pompeii: the untold Roman Rescue is showing at the WA Maritime Museum from Friday 22 September.

Australian National Maritime Museum logo.

This article was sourced with permission from the Australian National Maritime Museum.

It originally appeared in Signals 118 (March 2017). Read more maritime investigations and stories in the quarterly magazine Signals, now available to download for iPad via the App Store.