The history of ancient Rome—originally a city-state of Italy, and later an empire covering much of Eurasia and North Africa from the 9th century BC to the 5th century AD—was often closely entwined with its military history. The core of the campaign history of the Roman military is the account of the Roman military's land battles, from its initial defence against and subsequent conquest of the city's hilltop neighbours in the Italian peninsula, to the ultimate struggle of the Western Roman Empire for its existence against invading Huns, Vandals and Germanic tribes after the empire's split into East and West. Despite the later Empire's encompassing of lands around the periphery of the Mediterranean Sea, naval battles were typically less significant than land battles to the military history of Rome, due to its largely unchallenged dominance of the sea following fierce naval fighting during the First Punic War.

The Roman army battled first against its tribal neighbours and Etruscan towns within Italy, and later came to dominate much of the Mediterranean and further afield, including the provinces of Britannia and Asia Minor at the Empire's height. As with most ancient civilisations, Rome's military served the triple purposes of securing its borders, exploiting peripheral areas through measures such as imposing tribute on conquered peoples, and maintaining internal order.^[1] From the outset, Rome's military typified this pattern, and the majority of Rome's campaigns were characterised by one of two types: the first is the territorial expansionist campaign, normally begun as a counter-offensive,^[2] in which each victory brought subjugation of large areas of territory and allowed Rome to grow from a small town to the third largest empire in the ancient world, encompassing around one quarter of the world's total population;^[3] the second is the civil war, examples of which plagued Rome right from its foundation to its eventual demise.

Roman armies were not invincible, despite their formidable reputation and host of victories:^[4] over the centuries the Romans "produced their share of incompetents"^[5] who led Roman armies into catastrophic defeats. Nevertheless, it was generally the fate of even the greatest of Rome's enemies, such as Pyrrhus and Hannibal,^[6] to win the battle but lose the war. The history of Rome's campaigning is, if nothing else, a history of obstinate persistence overcoming appalling losses.^[7][8]

Technological history of the Roman military

The technology history of the Roman military covers the development of and application of technologies for use in the armies and navies of Rome from the Roman Republic to the fall of the Western Roman Empire. The rise of Hellenism and the Roman Republic are generally seen as signalling the end of the Iron Age in the mediterranean. Their iron-working was enhanced by a process known as carburization, the Romans made use of the better properties in their armaments, and the 1300 years of Roman military technology saw radical changes in technology. The Roman armies of the early empire were much better equipped than early republican armies. Metals used for arms and armour included primarily iron, bronze and brass. For construction, the army used wood, earth and stone. The later use of concrete in architecture was widely mirrored in Roman military technology, especially in the application of a military workforce to civilian construction projects. ^[1]

Origins and development

Much of what is described as typically Roman technology, as opposed to that of the Greeks, comes directly from the Etruscan civilization, which was thriving to the North when Rome was just a small kingdom. The Etruscans had perfected the stone arch, and used it in bridges as well as buildings. A part of later Roman technologies were taken directly from Greek civilization.

After the absorption of the ancient Greek city states into the Roman Republic in 146 BC, the highly advanced Greek technology began to spread across many areas of Roman influence and supplement the Empire. This included the military advances the Greeks had made, as well as all the scientific, mathematical, political and artistic developments.

New materials

However, the Romans made many significant technological advances, such as the invention of hydraulic cement and concrete. They used such new materials to great advantage in their structures, many of which survive to this day, like their masonry aqueducts such as the Pont du Gard and buildings such as the Pantheon and Baths of Diocletian in Rome. Their methods were recorded by such luminaries as Vitruvius and Frontinus for example, who wrote handbooks to advise fellow engineers and architects. Romans knew enough history to be aware that widespread technological change had occurred in the past and brought benefits, as shown for example by the Naturalis Historia of Pliny the Elder. That tradition continued as the empire grew in size and absorbed new ideas. Romans thought of themselves as practical, so small-scale innovation was common (such as the development of the ballista into the repeating ballista). The traditional view is that their reliance on a plentiful slave labour force and a lack of a patent or copyright system have both been cited as reasons that there was little social or financial pressure to automate or reduce manual tasks. However, this view is being challenged by new research that shows they did indeed innovate, and on a wide scale. Thus the watermill had been known to the Greeks, but it was the Romans who developed their efficient utilisation. The set of mills at Barbegal in southern France were worked by a single aqueduct, which drove no less than 16 overshot mills built into the side of a hill. They probably were built by the army and supplied flour to a wide region. Floating mills were also used to exploit fast flowing rivers.

Pont du Gard

Water power

The Romans also used water power in an unexpected way during mining operations. We know from the writings of Pliny the Elder that they exploited the alluvial gold deposits of north-west Spain soon after conquest of the region in 25 BC using large-scale hydraulic mining methods. The spectacular gold mine at Las Medulas was worked by no less than 7 long aqueducts cut into the surrounding mountains, the water being played directly onto the soft auriferous ore.

The outflow was channelled into sluice boxes, and the heavier gold collected on rough pavements. They also developed many deep mines, such as those for copper at Rio Tinto, where Victorian mining developments exposed the much earlier workings. Dewatering machines such as Archimedean screws and reverse overshot water wheels were found in situ, one of which is on show at the British Museum. Another fragmentary example was recovered from the Roman gold mine at Dolaucothi in west Wales, and is preserved at the National Museum of Wales in Cardiff. The army were at the forefront of development of gold mines, since the metal was imperial property, and developed the Dolaucothi mines from the outset by establishing a fort there that was known as Luentinum. They had the expertise to build the infrastructure of aqueducts and reservoirs, as well as control production.

Panoramic view of Las Médulas

The period in which technological progress was fastest and greatest was during the 2nd century and 1st century BC, which was the period in which Roman political and economic power greatly increased. By the 2nd century, Roman technology appears to have peaked.

Roman implementation of technology

The Romans advanced military technology significantly, and implemented it on a massive scale. From a few early models of ballista from Greek city-states the Romans adopted and improved the design, eventually issuing one to every century in the legions.

To facilitate this organisation, an engineering corps was developed. An officer of engineers, or praefectus fabrum, is referenced in armies of the Late Republic, but this post is not verifiable in all accounts and may have simply been a military advisor on the personal staff of a commanding officer ^[2]. There were legion architects (whose rank is yet unknown) who were responsible for the construction of war machines who would also assure that all artillery constructions in the field were level. Ensuring that constructions were level was the job of the libratores, who would also launch missiles and other projectiles (on occasion) during battle ^[3]. The engineering corps was in charge of massive production, frequently prefabricating artillery and siege equipment to facilitate its transportation ^[4]