When we think of Rome, we think of its empire extending into Spain, France and out west into Turkey, but it had to grow and conquest to reach that, and it took several centuries to do. After the kings of Rome were overthrown, or removed, in about 510 BC, there was an expansionary century for Rome where they established themselves as the dominant city in the Latium League and expanded their land-holdings, which is important for a yeoman military, however in 390 BC all these gains were lost with a successful Gallic invasion of Italy - and seizing of Rome.
I am going to focus on the military aspects of this period, to determine the external and internal pressures up against Rome. With the establishment of the Republic, the Etruscans were on the wane, while to the south was the Latium League, of which Rome was an on and off partner and signatory. Other groups that posed military threats included the Hernici, the Sabines which were probably being pressed from the north by Gauls and moving south under that pressure, the Aequi and the Volsci. Rome established treaties with the Latins and Hernici, and together they resisted the advances of the other tribes.
I am never sure how much of this is conquest, natural expansion, or just immigration. For instance the Gauls were constantly pressing down from the north, and it appears that a constant source of migration was from the Russian steppes into western Europe. Was the constant warring an aspect of culture or civilisation at the time? Or was it just a form of migration, albeit a violent form? I don't know.
Alot of the tales of the military campaigns from the period come from tradition, so they often have a political, as well as mythical, aspect to them, such as explaining away Roman failure in a way that is palatable to Roman readers. It appears that the Volsci and Aequians advanced into Latin and Hernici territory, a campaign in which Rome took part, and upon losing Lucius Mincius, precipitated the crisis that led to the legend of Cincinnatus. Who dropped the plough in a time of crisis, took dictatorial powers and retook the valley that Mincius was lost in. Seventeen days later Cincinnatus was back to his plough.
The big battles were in the north against the city-state of Veii - an Etruscan city which was only about twelve miles away from Rome. As part of this wider war, in which Rome expanded northward, the Etruscan city of Fidenae was taken through siege before Veii was besieged about twenty years later. In that time Fidenae revolted at least once.
All this fighting went on between 493 and 390 BC. A decisive battle against the Aequi was not until 431, and the same with the Volsci, who were pushed back constantly from the same year onwards. The battles with Veii seem to be in the latter part of the century, with Fidenae being taken in 435 BC and again, after a revolt, in 425 BC. Veii was also taken after a (probable) ten year siege in 396 BC. Interestingly, as the siege campaign went through summer and winter, the yeoman troops were payed for the first time - the beginnings of a Roman professional army.
H.H. Scullard writes that the end of this century's struggle left Rome on top politically, despite it having less land than the Latium League:
Whereas the Roman territory was a compact mass, the Latin possessions were scattered and often separated by Roman property. In these circumstances the Latins found common action difficult, so that a profound change came over th League. Rome almost unconsciously assumed the leadership. A city in distress would turn more readily to the united and ready forces of Rome than to the disunited Latins; and the Romans would often call on the Latins to supply their contingents without waiting to summon a federal council.So the Sabines never really made it far enough south to bother Rome, but caused downwards pressure on other tribes. The Aequi and Volscans were beaten by a treaty between Rome, the Latins and Hernici such that they were no longer military threats; and the Etruscan cities, of which Veii was a large one, were now susceptible to Roman expansion. To top it off, Rome came out on top politically amongst its allies and had an efficient and organised military. But this is still really only local power and influence. Rome is still pretty small and despite the conquering of Veii, it is a city that is only twelve miles away. This isn't the same projection the Roman legions in Caesar's time have. This fragility is shown with the invasion of Brennus' celts. The Gauls were strong enough militarily that they were able to take northern Italian cities. When Brennus marched on Rome he did so with an army of approximately 30,000 to Rome's 10,000. Scullard comments that this Roman army was probably the largest it had put into the field in the history of Rome to that point! Rome was taken by the Gauls, who appeared more interested in plunder than land, being bought with gold. The fact was that Roman power had been completely destroyed by the defeat at the hands of the Gauls. The city was taken, the treaties with the Latins and Hernici collapsed, the army was destroyed, and the territorial gains of the last century's fighting gone; and those that remained were under expansionary threat from neighbours. Part of Rome's appeal is its resilience and it took fifty years to win back all that was lost in 390 BC to the Gallic invasion. Scullard writes:
it was largely owing to Roman courage in defeat and resolution in rebuilding a barrier against the north that France and not Italy became the home of the Celts.cam
