Ancient times and the early Christian period
Thanks to trade routes and communications, the ancient peoples of the Bronze and Iron Ages living in the land which is present-day Croatia were in touch with the artistic output of the Greeks and Etruscans from as early as the 8th century BC, but it was only with the arrival of the Greek colonists in the 4th century BC that conditions were established for the wider spread of Classical civilisation on the eastern Adriatic coast. Through the Greek colonies, such as Issa (Vis) and Pharos (Stari Grad, on the island of Hvar), Greek influence spread, as evidenced in the script, coinage, trade, parcelisation of land and building of city walls.
From the 2nd century BC onwards, Rome gradually established power and created administrative regions – the provinces of Dalmatia and Pannonia. Cultural and economic development with the characteristics of Roman civilisation (urbanism, architecture, sculpture, cults, coinage and trade) first arose on the Adriatic coast, then further in the deep hinterland. Many settlements took on the characteristics of Roman towns (Parentium/Poreč, Salona/Solin, Iadera/Zadar, Narona/Vid, near Metković, Aenona/Nin, Varvaria/Bribir) and forum complexes were built with basilicas, curias, thermal spas, etc. There were also grand public buildings, particularly theatres (Pola/Pula, Salona/Solin) and amphitheatres (Pola, Salona, Burnum/Ivoševci, near Kistanje).
Thermal spa towns sprang up in the Pannonian area (Aquae Iasae/Varaždinske Toplice), as did important towns, only a little of whose architecture has been preserved (Siscia/Sisak, Marsonia/Slavonski Brod, Mursa/Osijek, Cibalae/Vinkovci). A special place among all these was held by Diocletian's Palace in Split. Marked achievements of Roman and Hellenistic building were the country estates of Brijuni and also Polače on the island of Mljet, roads (Salona-Sirmium, Emona-Sirmium), bridges and aqueducts (Diocletian's Aqueduct).
After Constantine's edict on tolerance was issued in 313, early Christian art began to flourish in a natural symbiosis with Classical culture. The most important monuments of early Christian sacred architecture are found in Salona, and there are particularly important early Christian graveyards north of the town (Marusinac, Manastirine, Kapljuč). After the Byzantine Empire, the eastern heir of the Roman Empire, became the main political force in Italy and on the eastern Adriatic in the mid-6th century, a series of forts were built to defend and control the shipping route, of which the Byzantine castrum on Veli Brijun is a fine example. The Euphrasian Basilica complex in Poreč is another magnificent architectural monument from that period.
At the end of the 6th century, Classical civilisation began to wane in Croatia. The reason for this was the economic disintegration of the towns due to increasingly frequent raids by 'barbarian' tribes.