Romans[1] subdued the Greek colonial cities in the 3rd century BC. They imposed an organization based on a military-economical system.The most perfectly preserved Roman monuments are in Pola (Pula); founded in the first century dedicated to Julius Caesar. Numerous rustic villas, and new urban settlements (the most impressive are Verige in Brijuni, Pula and Trogir - formerly Tragurion) demonstrate the high level of Roman urbanization.It is full of classical Roman art such as: stone walls, two city gates, two temples on the Forum, and remains of two theaters, as well as the Arch from the year 30 AD, and the temple of Augustus built in the years 2 to 14 AD, and finally the Fluvian Amphitheater (so called - Arena) from the 2nd century.The early Middle Ages brought the great migration of the Slavs and this period was perhaps a Dark Age in the cultural sense until the successful formation of the Slavic states which coexisted with Italic cities that remained on the coast, each of them modelled after Venice.Furthermore, the Romans subdued the Illyrians in the first century BC and organized the entire coastal territory by transforming the citadels into urban cities.On its pathways, cellars, domes, mausoleums, arcades and courtyards we can trace numerous different art influences from the entire Empire.There were at least thirty urban cities in Istria, Liburnia and Dalmatia with Roman citizenship (civitas).The best-preserved networks of Roman streets (decumanus/cardo) are those in Epetion (Porec) and Jader (Zadar).Near the city emperor Diocletian, born in Salona, built Diocletian's Palace around year the 300 AD, [2] which is the largest and most important monument of late antique architecture in the world.It had numerous basilicas and necropolises, and even two saints: Domnius (Duje) and Anastasius (Stas).In the 3rd century AD, the city of Salona became the largest (it had 40,000 inhabitants) and most important city of Dalmatia.