What Was a Naumachia? Ancient Rome’s Naval Gladiator Spectacle
A naumachia, Latin from the Greek ναυμαχία, meaning “naval combat”, was a Romans’ dramatic reenactment of sea warfare. These events took place in purpose-built water arenas, known as naumachiae, often with real ships and fighters on display. As public spectacles, they offered dramatic entertainment and reinforced imperial authority.
Julius Caesar’s First Naumachia in 46 BCE
The earliest recorded naumachia dates to 46 BCE, staged by Julius Caesar during his grand quadruple triumph. He had a large basin excavated beside the Tiber River that could hold actual warships: biremes, triremes, and quinqueremes. Caesar populated this water arena with 2,000 fighters and 4,000 rowers, all prisoners of war. The restaged naval combat behind him symbolized his power and military achievements.
Augustus’ Expanded Naumachia in 2 BCE
In 2 BCE, Emperor Augustus upped the ante during the inauguration of his Temple of Mars Ultor (“Mars the Avenger”). Drawing on Caesar’s template, he built a massive 400‑by‑600‑yard basin across the Tiber. This version portrayed a battle between Greeks and Persians. According to the Res Gestæ (#23), 3,000 men, excluding the rowers, fought in 30 ram‑equipped ships, along with several smaller support vessels.
Claudius’ Naumachia on Fucine Lake, 52 CE
The most impressive naumachia arguably came from Emperor Claudius in CE 52. He chose Fucine Lake, a real body of water, to celebrate his recent drainage engineering project. With a hundred ships and 19,000 combatants, mostly condemned prisoners, this naval show dwarfed earlier events. According to Suetonius, these doomed fighters saluted the emperor with “morituri te salutant” (“those who are about to die salute you”). There’s no record of that phrase being used anywhere else.
Why Naumachiae Were More Violent Than Gladiator Fights
Naumachiae offered a far bloodier alternative to one-on-one gladiator duels. Instead of individual showdowns, they featured large-scale group battles between makeshift armies. The participants were often death-row prisoners with little formal training in combat. The naumachia was a natural evolution of Roman “group combat” spectacles, translating that brutality onto water.
Historical Drama on Water: Themes and Factions
These naval battles weren't just random violence. Organizers choreographed them around historical or mythological naval conflicts. Each side in the battle wore the identity of a notable seafaring power. Caesar’s naumachia saw Egyptians and Tyrians face off. Augustus staged Persians against Athenians. Claudius cast Sicilians against Rhodeans. By staging these themed battles, emperors tied their spectacles to larger narratives of Mediterranean history.
Why Emperors Used Naumachiae for Special Occasions
Naumachiae demanded a ton of resources; massive basins or lakes, scores of ships, thousands of fighters and rowers. This made them far more extravagant and costly than most public entertainments. Emperors reserved them for their most impressive public celebrations: temple dedications, monumental inaugurations, or political triumphs. Staging a naumachia showed off both engineering might and elite status.
The Legacy of the Word “Naumachia”
Over time, the term “naumachia” not only referred to the staged naval battles themselves but also to the water basins built for them. The name, taken directly from Greek ναυμαχία, came to mean both the spectacle and the artificial arena it required. Today, the word brings to mind Rome’s grandest and deadliest maritime dramas.
The Earlies
The earliest naumachia attributed to Julius Caesar likely took the form of a straightforward basin carved into the lowlands along the Tiber River. Fed directly by the river, its exact site remains uncertain, though historians typically suggest it stood on either the Trastevere shore or the edge of the Campus Martius.
The naumachia built by Augustus is set out in greater detail. In his own Res Gestae (23), the emperor notes that the basin measured 1,800 by 1,200 Roman feet - around 533 by 355 meters. Pliny the Elder adds another layer, in his Natural History (16.200), stating that Augustus commissioned a central island within the basin. Likely rectangular, it connected to the shore by a bridge, and may have hosted elite spectators.
Given that a Roman trireme measured roughly 35 by 4.9 meters, fitting thirty such ships into the basin would have offered limited room for maneuvering. Crews numbered around 170 oarsmen plus 50 to 60 soldiers per ship. If grapes into these figures, fitting 3,000 combatants on Augustus’s thirty ships meant crowding each vessel with more soldiers than actual warships would carry. As a result, the show paid less attention to naval tactics than to the vessels’ static presence and the close-quarter fighting on board.
Claudius’s naumachia presented a different scenario. He showcased two fleets, each composed of 50 vessels, mimicking Rome’s real naval fleets at Misenum and Ravenna. Using part of Lake Fucino, Claudius enclosed a section with pontoons, giving enough open space for the ships to maneuver and ram one another. Here, the event genuinely simulated naval warfare.
The water for Augustus’s basin came via a purpose-built channel, as described by Sextus Julius Frontinus in De aquaeductu urbis Romae (11.1–2), called the Aqua Alsietina. This aqueduct later supplied nearby gardens in the Trans Tiberim region. Archaeologists have unearthed parts of it on the Janiculum hill, below the monastery of San Cosimato. Scholars disagree on the exact site of the basin, but current theory places it between modern Via Aurelia and the church of San Francesco a Ripa, nestled in the Tiber’s curve. A republican-era viaduct near San Crisogono on Via Aurelia might also have channeled water to the basin.
Augustus’s basin was short-lived. Suetonius (in Augustus, 43.1) reports that it was partly replaced by the nemus Caesarium, later called the "forest of Gaius and Lucius" in honor of Augustus’s grandsons, according to Dion Cassius (66.25.3). This wooded area was likely developed with buildings by the end of the first century.
A new twist arrived under Nero, who staged naumachiae inside a wooden amphitheatre built in the Campus Martius. Both Suetonius (Nero, 12.1) and Dio Cassius (Roman History, 61.9.5) describe such a spectacle in CE 57, marking the amphitheatre’s inauguration soon after the Julio-Claudian line ended. Nero hosted another naumachia in CE 64, this one preceded by wild hunts, followed by gladiatorial contests and a lavish feast, as recounted by Dio Cassius (62.15.1). Details about the structure remain vague, but it was almost certainly the same wooden arena and survived through the Great Fire of Rome - no records suggest its destruction sooner.
When the Colosseum opened in 80 CE, Emperor Titus held two naumachiae, mock naval battles meant to impress. The first took place in the Augustinian basin. Thousands of combatants recreated maritime warfare. The second show happened within the new amphitheatre itself, according to Dio Cassius. He describes both events in his Roman History (Book LXVI, 25, 1–4).
A few years later, Emperor Domitian continued the tradition. Suetonius records that Domitian staged a naumachia inside the Colosseum around 85 CE. He organized another in 89 CE in a man-made basin dug beyond the Tiber River. Stones from that excavation were later used to rebuild parts of the Circus Maximus after a fire damaged it on two sides (Suetonius, Domitian, IV, 6–7). It's believed that Domitian used the interval between these two sea battles to finish constructing the underground network of rooms - the hypogeum - under the Colosseum. Once the hypogeum was complete, water spectacles in the arena stopped.
The Colosseum’s arena itself measured only 79.35 × 47.20 meters. That’s much smaller than the Augustinian basin. This means naumachiae inside the amphitheatre couldn’t match the grandeur of earlier shows. Rather than actual ships sailing, they likely used replicas or stage props that looked like vessels. These props may have been mechanical, capable of simulating things like shipwrecks. Both Tacitus and Dio Cassius mention the use of such effects on stage and in arena shows (Annales, XIV, 6; Roman History, LXI, 12).
Holding enough water to float vessels in an amphitheatre raises engineering questions. After a naumachia, the arena needed to be drained quickly to make room again for gladiatorial combat or beast hunts. Fast transitions between water spectacles and land events were part of the show. Dio Cassius points to such rapid shifts during Nero’s naumachia (Roman History, LXI, 9, 5), and Martial highlights the spectacle of Titus’ show in his Book of Spectacles (XXIV).
Unfortunately, written accounts don’t explain how the water was managed, and the Colosseum’s hypogeum has been altered over time, leaving no clear archaeological evidence. But amphitheatres in two other Roman cities, Verona and Mérida, offer clues.
In Verona, the arena has a central pit deeper than other service rooms beneath its floor. This pit served as a basin. Two conduits connected to it: one ran under the west gallery and needed an aqueduct link to fill it, since it wasn’t tied to drainage. The second conduit sat lower and drained water into the Adige River. This setup hints at how Roman engineers controlled water levels in amphitheatres.
Mérida’s amphitheatre includes another kind of basin, about 1.5 meters deep, shallow enough that it can’t be mistaken for a cellar. It has stairs for access and is lined with materials used in Roman baths or pools. Two conduits supplied and emptied water; the western one linked to the nearby San Lazaro aqueduct. Still, the basin measured only 18.5 × 3.7 meters - large enough only for simple water displays.
These dimensions show that naumachiae at these sites could only be modest naval spectacles. If the Colosseum had a similar shallow basin before the hypogeum was built, its shows would have involved minimal depths - just enough water to keep floating ships afloat. That meant the mock battles might have featured small-scale replicas afloat in a thin layer of water, not full-scale maneuvers.
The Rise and Change of Roman Naumachiae
As technology advanced, Romans could stage naval battles - naumachiae - more often. Early ones were rare and grand, with the first three spread out by about 50 years each. But then, six more took place in just 30 years. These became regular features of amphitheatre games. They needed fewer ships and fighters, so they happened more often, though they lost pomp. Art from Nero’s time through the Flavian dynasty shows roughly 20 depictions of naval fights, mostly in the Fourth Style. That illustrates how ordinary these events had become.
Naumachiae Disappear from Texts After the Flavians
After the Flavian era, mentions of naumachiae nearly vanish from written records. One reference appears in the late and not very reliable Augustan History. Beyond that, only the fasti, or town records, of Ostia note a single basin used for a naumachia. That happened in 109 CE, when Emperor Trajan opened it. Archaeologists discovered this basin in the 18th century within modern Vatican City, northwest of Castel Sant’Angelo. Though often mistaken for the Circus of Hadrian due to its shape and its proximity to Hadrian’s mausoleum, it’s now recognized as the Naumachia Vaticana. Excavations have exposed the full plan. It included tiered seating for spectators but covered only one-sixth of the area of Augustus’s earlier venue. With no written record beyond its inauguration, archaeologists assume it saw use only during Trajan’s reign.
Evidence of Continued Use into the 5th Century
Roman and medieval clues suggest the site remained in use long after Trajan. Place names like naumachia and dalmachia persisted into medieval maps, and remains of seating around the perimeter indicate regular performances. Ostian records mention Trajan’s opening featured 127 pairs of gladiators. That suggests that, unlike large prisoner fleets in open waters, this small basin favored gladiatorial-style naval combats: one-on-one duels. Such simpler, limited shows could have carried on for centuries without being recorded, as they lacked the scale and spectacle of earlier events.
Provincial Echoes: Naval Displays Beyond Rome
Outside Rome, memories of naumachiae appear in more restrained forms. In the Greek world, a game called naumaciva appeared in the Panathenaic Games from the Flavian period on. It replaced traditional regattas, suggesting a local version of naval reenactment. Poet and teacher Ausonius even mentions a small-scale naumachia on the Moselle River involving local youths. These provincial spectacles were harmless naval shows, far removed from the imperial pageantry of Rome.
Renaissance Scotland: Lochside Naval Spectacles
In 1562, at a wedding in Scotland, guests witnessed a naumachia staged on a loch in Holyrood Park to celebrate Lord Fleming’s marriage. Nineteen years later, in 1581, another took place on the Water of Leith during the union of James Stewart, 2nd Earl of Moray, and Elizabeth Stewart. These displays revived the ancient Roman naval battle tradition in a local, festive way.
England’s River Pageants: Thames and Bristol
A grand naumachia was held on the Thames in February 1613 to celebrate Princess Elizabeth’s marriage to Frederick V of the Palatinate. That same year, in June, Anne of Denmark visited Bristol and attended a staged naval fight on the Avon and Frome rivers at Canon’s Marsh. On June 7, she viewed a mock conflict between an English ship and two Turkish galleys. The finale included actors playing Turkish captives kneeling and begging mercy. Anne reportedly laughed at their costumes and expressions, finding them amusing. Poet Robert Naile described the scene in verse, noting that the Turkish roles were performed by sailors “worthy brutes, who oft have seen their habit, form and guise.”
European Royal Festivals: France and Italy
In 1550, a naumachia was performed in Rouen for King Henry II of France. Later, in 1589, Florence hosted one in the courtyard of the Palazzo Pitti to celebrate the wedding of Grand Duke Ferdinando I de’ Medici and Christina of Lorraine. An etching by Orazio Scarabelli captured the spectacle, preserved in a collection commemorating the festivities.
Naumachiae in Georgian England
During the Georgian period, English aristocrats recreated Roman-style naval battles on their private lands. Francis Dashwood, the 11th Baron le Despencer, built a swan-shaped artificial lake at West Wycombe. He staged small-ship naumachiae there, even adding a fort on the shore so he could participate in the mock naval combat.
Continental and Later European Celebrations
In 1755, Valencia‑ Spain honored Saint Vincent Ferrer’s canonization centenary with a naumachia held between the bridges over the Turia River. Then, in 1807, Milan hosted a naumachia for Napoleon. Paris’s Parc Monceau features a permanent ornamental naumachia pool with surrounding colonnade. In the 18th and 19th centuries, English parks often included model‑ship naval battles, also labeled naumachiae. Peasholm Park in Scarborough continues this tradition with live events that emulate historic sea fights. Smaller-scale “aqua dramas” in theatres also gained popularity during this time.
Modern Revival: New York’s 2009 Naumachia
In 2009, New York artist Duke Riley revived the ancient spectacle at the Queens Museum of Art. His modern naumachia brought the tradition into the contemporary art world, demonstrating its enduring appeal and flexibility, even five centuries after its European origins.
