Dalmatia has been inhabited since very ancient times.
The oldest phase so far attested by significant findings is the Neolithic one, since important evidence from the Paleolithic is lacking so far and the same is true for almost the entire Balkan territory corresponding to the former Yugoslavia.
Neolithic tools and weapons have been found in the vicinity of Zadar, Neolithic cave stations have been discovered on the islands of Lesina and Korčula; Neolithic vases and other finds of engraved and painted ceramics of oriental origin, such as the beautiful ceramic, called Danilo, have been found in the vicinity of Šibenik.
Other important stratigraphic series have been recently discovered on the island of Lagosta.
Judging from the finds from Lesina and Sebenico, the Dalmatian coast was already in ancient times part of a vast cultural circle that included the Aegean, Sicily, the Lipari Islands and Puglia.
If not for the Neolithic, but certainly for the Eneolithic we can speak of the existence of an "amber road" that from the seas of northern Europe, through the area of Fiume, touched Lesina and then reached Corfu and from there the Peloponnese and Sicily.
Evidence of the Bronze Age can be found in the interesting “castellieri” scattered along the entire Adriatic coast from the Gulf of Trieste to the Boka Kotorska Bay.
These are typical settlements located on hills and equipped with mighty stone walls.
In this period, the presence of Indo-European peoples called Illyrians began to establish themselves throughout central-southern Dalmatia, who lived alongside peoples of the same lineage, Thracians and Greeks, inhabiting the south-eastern areas of the Balkan Peninsula.
The Iron Age civilization appears divided in Dalmatia into two periods from 1000 to 350 BC and from 350 to 100 BC.
The most important example, according to the findings, is represented by the Glasinac culture (a plateau in the vicinity of Sarajevo) where numerous necropolises with thousands of tombs were found.
The breadth of the relational horizon of this culture is demonstrated, among other things, by the discovery in the area of some Etruscan helmets.
In fact, the territory of Glasinac does not geographically fall within Dalmatia, but its territory became part of the Roman province of Dalmatia, maintaining constant contacts with it.
The second period of the Iron Age civilization in Dalmatia and the Balkans was characterized by the Celtic invasion which influenced in many ways the territories inhabited by the Thracians and the Illyrians.
The most significant evidence of the Iron Age in Dalmatia is found in Nona (Nin in Croatian), an agricultural centre approximately 25 kilometres north of Zadar, where a necropolis with around seventy tombs was discovered.
The materials found and datable between the 8th and 4th century BC, show close connections with those of the Piceno territory.
However, it is difficult to reconstruct a precise overall picture of the indigenous peoples of Dalmatia prior to Greek colonization and Roman conquest. The various sources of Appian, Strabo, Cassius Dio, Pliny and Ptolemy do not help in this sense, since it often happens that the same ethnic group is defined by different authors with various names.
The same name of illyri is used improperly in several contexts creating confusion.