What things did the Romans introduce to the countries they invaded?

Answer 1

First of all, countries in the modern sense of the word (nation-states) did not exist in antiquity. There were three main types of state formations. One was kingdoms and empires. Another was territories of ethnic groups named after the group. These could be of a size similar to a county (as with some ethnic groups of central Italy) or a regional size. They could be collections of city-states as with Etruria (land of the Etruscans) and Latium (land of the Latins, Rome was one originally of these city-states) federations of tribes (as with Samnium, land of the Samnites, which was a federation of four Samnite tribes) or ethnic areas where each tribe had its own state, as with the Gauls of northern Italy.

The Romans did not change many things in their conquered territories. through tolerating the religions and customs of the conquered peoples. They allowed them to continue to worship their religions, follow their customs and use their customary laws at the local level. They also let the local ruling classes run most of the local affairs. The role of the provincial governors of the provinces (conquered territories) was restricted to defence and maintenance of the legions stationed in the provinces, tax collection, public works and the arbitration of disputes the locals could not resolve by themselves. This policy had two advantages: it reduced the administrative load of the provincial governors and it facilitated the integration of the locals into the ideology and the economy of the empire. A less tolerant policy would have led to too many rebellions and would have threatened the stability of the empire.

Changes which occurred in the conquered territories were the presence of Roman legions, especially in the border provinces, their integration into the trading networks of the Roman Empire and the construction of the famous Roman infrastructure: roads, including the famous stone-paved roads, the aqueducts, ports, dams, bathhouses, etc. Contact with Roman traders, trade with the Roman soldiers stationed in the provinces and the settlement of retired soldiers in the provinces led to various degrees of Romanisation in the conquered territories.

Answer 2

Roads, baths, law. bureaucracy, "citizenship" (they became citizens of Rome).