Iapydes

Alexander the Molossian, the Epirote king called to the aid of Taras, had claimed a victory over the Messapians between 333 BCE and 330 BCE.

The Messapians had joined forces with the Tarentines ater his death in 330 BCE to face an even greater force, that of Rome.

Taranto, attacked by the Lucanians in 304 BCE, asks for the help of Agathocles, who arrives in southern Italy and takes control of Bruttium (present-day Calabria), but is later called back to Syracuse.

Cleonymus of Sparta establishes an alliance with Taranto against the Lucanians in 303 BCE - 302 BCE, and fights against them.

To help Taranto against the Lucani, Cleonymus had gone as mercenary leader to southern Italy in 303 BCE with the backing of the Spartan administration..

There are two different accounts of his Italian expedition; one written by Diodorus Siculus and one by Livy, but the relations between the two sources are unclear.

The historian Thomas Lenschau supposes that they describe two different campaigns of Cleonymus: that one described by Diodorus Siculus would have taken place in 303 BCE and that one described by Livy in 302 BCE.

According to Diodorus Siculus, Cleonymus raises such a large army that the Lucani immediately conclude peace.

Then the Spartan prince takes the city of Metaponto and sails to Corcyra, which island he also quickly captures.

Learning that Taranto and other cities have broken with him, he sails back and is at first successful, but then he is defeated at a night attack.

As many of his ships are destroyed by a storm at the same time, he has to withdraw to Corcyra ion 303 or 302 BCE).

Probably in the next year (302 BCE) Cleonymus returns to Italy and—according to Livy—first conquers a city called Thuriae, location unknown, but Roman armies force him back to his ships.

The alliance with Taras and with Cleonymus of Sparta is essentially an anti-Roman campaign.

Thus, towards the end of the fourth century, Rome had become a common enemy for both the Iapygians and the Tarentines, even as far as ending the prolonged battles and causing them to make an alliance.

Tergeste, built mostly on a hillside that becomes a mountain at the head of the Adriatic Sea, was originally an Illyrian settlement but the town was later captured by the Carni; it falls to the Romans in 177 BCE.

Istria, the largest peninsula in the Adriatic Sea, located at the head of the Adriatic between the Gulf of Trieste and the Bay of Kvarner, is named for the Histri.

Classified in some sources as a "Venetic" Illyrian tribe, with certain linguistic differences from other Illyrians, the Romans describe the Histri as a fierce tribe of pirates, protected by the difficult navigation of their rocky coasts.

It had taken two military campaigns for the Romans to finally subdue them in 177 BCE.

Together with the Venetian part, the region is now called the X. Roman Region of "Venetia et Histria", the ancient definition of the northeastern border of Italy.

The eastern border of Italy, per ancient definition, is the river Arsia.

The eastern side of this river has been settled by people whose culture is different than Histrians.

Earlier influence of the Iapydes was attested here, while at some time between the fourth and first century BCE, the Liburnians extend their territory and it becomes a part of Liburnia.

On the northern side, Histria goes much further north and includes the newly garrisoned Tergeste (now the Italian city of Trieste, and the region of Venezia-Julia. For political reasons, modern Trieste and Venezia-Julia are not included in today’s Istria.)

The Romans had established their colony in Aquileia in 181 BCE and taken control of all Venetia in the north, thus expanding towards the Illyrian area from the northwest.

They had conquered Istria in the north of the eastern Adriatic coast, settled by tribe of Histri, in 177 BCE, while the Iapydes, the northern Liburnian neighbors, attacked Aquileia in 171 BCE, but these accidents have not involved the Liburnian territory.

The Liburnians probably keep away from direct conflicts with the Romans to safeguard their remaining naval activities.

The Romans in the second century BCE had subjugated various parts of Illyria, such as Histria in 177 BCE and the Ardaeian kingdom in 168 BCE, when they defeated the army of king Gentius.

Southern Illyriafrom 167 BCE had become a formally independent protectorate of the Romans, for whom the region has considerable strategic and economic importance.

It possesses a number of important commercial ports along its coastline, and has gold mines in its interior regions.

Illyria is also the starting point of the Via Egnatia, the great Roman road that runs from Dyrrachium (modern Durazzo), on the Adriatic, to Byzantium in the east.

Next came the interior of the western Balkans, accumulating in the wars with the Dalmatae in 156BCE  and 78 BCE, and in 129 BCE against the Iapydes.

Illyricum in 59 BCE after the Lex Vatinia had been assigned as provincia together with Cisalpine Gaul (zone of responsibility rather than the province as is understood today) to Caesar.

No province had been established until Octavius's wars in Illyricum during 35-33 BCE.

Caesar's assassination had encouraged the Illyrians to regain their liberty.

They refused to pay taxes and destroyed five cohorts of the army commanded by P. Vatinius, also killing the senator Bebius.

The Roman senate had charged Marcus Junius Brutus, one of the assassins of Caesar, to lead the army in Illyria and Macedonia.

He had marched in the winter of 42 BCE from Greece at the head of the army, through roads covered by snow, doubtless coming along the Via Egnatia in order to appear by surprise before the walls of Dyrrhachian, sick with exhaustion and the cold.

Brutus after this took Apollonia and Byllis, pursuing and breaking the power of Gaius Antonius, who withdrew to Buthrotum.

Octavius in 35 BCE had been compelled to revisit Illyrian lands yet again, this time Dalmatia.

At the head of ten legions, he had marched from the north and subjugated the Iyapedes, Liburnians and Pannonians.

The most difficult war proved to be with the Dalmatians, in which the young future emperor was wounded twice, as Suetonius writes, first in the knee with a stone from a slingshot and later when a bridge fell during the siege of the Iapydian city of Metulum.

Octavian in that siege had seen with his own eyes the bravery of the Illyrians.

After managing to conquer the upper part of the city, Octavian had asked the inhabitants to surrender their weapons, but they collected their women and children and locked them in the council building, putting guards around it and ordering them to set the building on fire if the men were to suffer any harm.

After taking these measures they assailed the Romans in desperation, but since they were down below and the Romans above, they were badly broken and all were killed.

The assembly guards then set the building on fire, as they had been ordered, and many women and children were burned to death; and even more threw themselves on the fire, along with their children.

Together with them the city was burned so completely, that although it had been a very large city, not a trace of it remains.

The first mention of the province of Illyricum had occurred in the context of the Augustan settlement of 27 BCE.

The province was subsequently enlarged as the Romans expanded their power in the region through a series of wars known as Pannonian wars (Bellum Pannonicum), fought from 12 BCE -9 BCE against group of peoples known as the Pannonians.

The taxes imposed by the Romans are greatly resented by the native Illyrians, who are frustrated by this new shift of power.

The Romans often treat the their subjects terribly, selling the women and children as slaves and destroying their settlements.

The turn of the millennium has also seen the recruitment of many Illyrian soldiers into the Roman army to fight against the Germanic tribes in the north.

The widening gap between the Roman government and its subjects in Illyricum leads ultimately to the great revolt that begins in the spring of CE 6, when several regiments of Daesitiates, natives of the area that now comprises central Bosnia and Herzegovina, are gathered in one place to prepare to join Augustus's stepson and senior military commander Tiberius in a war against the Germans.

Instead, the Daesitiates, led by Bato the Daesitiate (Bato I), mutiny and defeat a Roman force sent against them.