The eastern coastline is punctuated by a number of lakes connecting (but not always) to the Tyrrhenian Sea, the remnant of an ancient system of lagoons behind barrier beaches. The Corsicans refer to them under the name of Étang, "pool", although most are larger by far than an English pool. Marshland is also extensive on the coast requiring that cities be built inland from it. Malaria has historically been a problem near the marshlands and swamps of eastern Corsica. The fine barrier beaches are a recreational attraction.
The Tavignano River enters the commune to the northwest and exits into the Tyrrhenian Sea. Its lands include a delta, marshes to the south and the unconnected étang de Diane to the north. To the west, the étang de Terre Rosse is a lake and reservoir used to irrigate the plain.
Corsica had an indigenous population in the Neolithic and the Bronze Age but the east coast was subject to colonization by Mediterranean maritime powers: Greeks, Etruscans, Carthaginians, Romans. They typically built on an étang, which they used as a harbor. Alaliē (Ionic dialect) was placed between the southern end of the long Ētang de Diane and the Tavignanu River (ancient Rhotanos), slightly inland, but controlling the entire district including the mouth of the river. The site is partly occupied today by the village of Cateraggio (Corsican U Cateraghju) at the crossroads of national routes N200 and N198. N200 follows the Vallé du Tavignano into the interior mountains of Corte.
When the Etruscans took the district after its abandonment by the Greeks they settled further south along N198 in the vicinity of the village of Aléria, today primarily an archaeological site across the river from Cateraggio, where visitors and academics are quartered. Still south of there was the Etruscan necropolis, in today's Casabianda. Aléria takes its name from the Roman town placed there after the defeat of the Etruscans.
The entire district, however, is wider still, following the Corsican custom of including some mountains and some beaches in every district. It incorporates the agricultural lands of Teppe Rosse (to the west), the entire Étang de Diane and the Plage de Padulone east of Cateraggio, a former barrier beach. Since 1975 a series of laws have created the Casabianda-Aléria Nature Preserve, between the mouth of the Tavignanu and the Étang d'Urbinu, which is to the south.
The reserve to the south was initiated from the grounds of the former penitentiary of Casabianda in 1951. It was instituted in 1880 in a then pestilential area which it was hoped the prisoners could farm. It contained 1800 ha and 214 plots. Due to a high death rate from malaria, the agricultural experiment failed.
Although no settlements of urban density preceded the first Greek colony, Aléria is unlikely to have been altogether unpopulated. A chance find of an ancient trash pit at a location called Terrina about from the Étang de Diane fills in some of the details concerning pre-Roman habitation. The pit was excavated 1975-1981 by G. Camps, who found four levels and named the site after the most important, Terrina IV.
Terrina IV features a Middle Neolithic culture in which the use of cattle and pigs predominated, in contrast to the rest of the island, which kept mainly goats and sheep and grew more grain. The Chalcolithic, approximately 3500-3000 BC, arrived by easy transition. The population of the site manufactured arsenical copper and copper goods; moreover, a distinctive socketed crucible has been found throughout the Aegean and in the Levant. The window ends there.
The visible antique habitations at Aléria date to the Iron Age and are consistent with the history. Although ruins on the promontory were noted by Prosper Mérimée in 1839 they were only excavated in 1955 by Jean Jehass and Jean-Paul Boucher. By 1958 the excavators had uncovered the forum of the Roman city of Aleria, first occupied in the 1st century BC.
A pre-Roman, Etruscan necropolis was then discovered to the south (in Casabianda) containing more than 200 tombs. It was excavated 1960-1981. The necropolis had been in use mainly from the 6th to the 3rd century BC and was abandoned altogether with the construction of the Roman city, which started a cemetery to the north. No artifacts identifiably Etruscan have been found earlier than the 6th century BC; that is, the Etruscans were most likely intrusive at that time. If there was any Aegean Etruscan substrate it was not on Corsica.
Systematic excavation since 1955 has revealed wide-ranging contacts in the sixth century, through pottery shards in test pits, with Ionian, Phocaean, Rhodian, and Attic black-figure ware. The excavated necropolis of Casabianda's rock-cut tombs have revealed grave goods, from the Late Archaic period forwards, that include the finest works of art, in jewels, weapons, metalwares, bronze and ceramic plates and dishes in particular, Attic cups, rhytons, distinctive kraters decorated by some of the first rank Attic vase-painters.
Portable antiquities found in the Aléria commune are presented for public viewing in the Musée Jérôme Carcopino within Fort Matra at Aléria village.
Diodorus says that Aleria had a "beautiful large harbor, called Syracusium," that Calaris and another city, Nicaea, were on it, and that Nicaea had been built by the Etruscans. Syracusium can only be the Étang de Diane, a lake exiting to the Tyrrhenian Sea. As Aleria and Nicaea were trade rivals it seems unlikely that the Etruscans would have allowed the Phocaeans, who were ancient Greeks, access to Étang de Diane. Nicaea is generally identified with the La Marana district further north, where the Romans later built a city, Mariana, on the Étang de Biguglia, a better harbor. Diodorus says that the cities of Corsica were subject to the Phocaeans and that the latter took slaves, resin, wax and honey from them. Alaliē was then an emporium. Of the natives whom the Phocaeans subjugated Diodorus says only that they were "barbarians, whose language is very strange and difficult to be understood" and that they numbered more than 30,000.
At home Phocaea was the first city of Ionia to come under siege by the army of Cyrus, who were Medes commanded by Harpagus, in 546 BC. Requesting a cease-fire the Phocaeans took to their ships, abandoning the city to Harpagus, who allowed them to escape. Refused permission to settle Oenussae in the territory of Chios they resolved to reinforce Alaliē, but first made a surprise punitive raid on Phocaea, executing the entire Persian garrison. At this success half the Phocaeans reinhabited Phocaea; the other half settled in the vicinity of Alaliē.
In Corsica they were so troublesome to the Etruscans and to the Carthaginians of Sardinia that the two powers sent a combined fleet of 120 ships to root them out, but this force was defeated by 60 Phocaean ships at the Battle of Alalia in the Sardinian Sea, which Herodotus describes as a Cadmeian victory (his equivalent of a Pyrrhic victory) because the Greeks lost 40 ships sunk and the remaining 20 so damaged as not to be battle-worthy. Now unable to defend themselves the Phocaeans took to their remaining ships and sailed off to Rhegium, abandoning Alaliē. The Etruscans landed the numerous Phocaean prisoners and executed them, leaving the bodies where they lay until the oracle compelled a proper burial. As the Carthaginians were not then interested in Corsica, the Etruscans occupied Alaliē and took over dominion of the island, which they held until the Romans took it from them.
The Etruscans continued to use the necropolis. Subsequently the Etruscan population must have assimilated to a new Roman population in parallel with the assimilation of Etruscans on the mainland. The Etruscan language disappeared and it must have been starting from that time that the island began to acquire its Latin language.
Under the late Roman Republic the Romans decided to build a major naval base on the shores of Étang de Diane. Starting in 80 BC under Sulla as dictator they rebuilt the city on the promontory at Aléria, naming it Aleria. The city rose to prominence under Augustus, becoming the provincial capital of Corsica. Major fleets were stationed on the étang. Ptolemy mentions it but says little about it, only mentioning "Aleria Colonia", the Rotanus River and Diana Harbor. He lists the "native races" inhabiting the island, but their geographical coordinates do not match those of Aleria; perhaps the Roman town was not considered among them.
In the later Roman Empire the port and the city declined. It never recovered from a disastrous fire of 410 AD and in 465 was sacked by the Vandals. Subsequently it became a small village of no interest to any major power. These events must mark the end of its classical antiquity. It was buried bit by bit by the Tavignano and the Tagnone, which also created the deadly marshes. The region became subsumed under a Christian parish.
In the 13th century AD Aleria became of interest to the Republic of Genoa. By that time the Latin language was gone but it had developed into Corsu on Corsica in parallel with the development of the other Romance languages. Aleria was the see of a bishop down to the French Revolution. At the end of the Ancien Régime, the bishop no longer lived in Aléria, but in Cervione.
The commune of Aléria was created in 1824, but it did not truly begin to revive until after 1945, after the allies (chiefly American) had undertaken to eradicate malaria (1944). An organization, SOMIVAC (Société d'aménagement pour la mise en valeur de la Corse) was created in 1957 to resurrect agriculturally the entire eastern plain under government sponsorship. It had great success in developing the region. Meanwhile a massive archaeological effort had gotten underway in 1955.