It is a delightful irony that the word Rome is Etruscan and it was the Romans who called the Etruscans, Etruscans. They referred to themselves as Rasenna and were a thriving, rich and influential association from the 8th to the 3rd centuries BCE when it became a part of the Roman Empire.
It existed in an area which corresponds approximated with modern Tuscany, south of the Arno river, western Umbria and northern and central Lazio, but at its height, for about 200 years it extended all the way up to the border with Gaul and well beyond what is now Venice in the north-east. Southwards it reached down almost to what is now known as Naples.
The Etruscan league was a confederation in the sense of a Greek city-state. Each of the cities was independent and not above warring with each other when needs must. The twelve main cities which constitute the dodecapolis show the closeness to Greek culture and organization at a time when Etruria was a power on the Tyrrenhian Sea.
What the cities did all share were a common language, religion and a general culture, much of which was subsumed into Roman culture and became what we associate with Rome.
Trade and coastal development
By the 7th century BCE trade was well established across the Mediterranean leading to a more robust and changing culture for the cities on the coast. Craftsmen from the Levant and Greece settled into the area, especially in the port of Pyrgri in Cerveteri. The incoming craftsmen had an effect on language and religion and also the alphabet and as a result, continue to have an effect to this day.
By 540 BCE the Etruscans had contrived a dominance of the sea to the extent the Greeks referred to them as pirates. Nevertheless, their dominance made them rich especially as they really began to exploit the natural coastal resources.
However, it was to be relatively short-lived as in Syracuse, Dionysius I was beginning to stretch his muscles and attacked and destroyed many of the Etruscan ports.
4th Century BCE
It was the first nail in the coffin. There was a resultant loss of trade, not surprisingly as there were no ports. Nevertheless, Etruria may still have had some larger influence. Some of the legendary Roman kings ostensibly came from modern-day Tarquinia, but things began to change in the 4th century when the neighbor to the south was no longer content to be a lesser power.
It was a slow death for Etruria, including sieges and battles, but like much of the rest of Europe, it was no match for the power and magnificence of the Roman army. An altogether more organized and professional force.
By 280 Tarquinia, Orvieto and Vulci had fallen. Cerveteri followed in 273 one of the last cities to hold out against what was now the Roman Empire.
Normally the Romans took their civilization to the rest of the world. Not so with the Etruscans.