To what extent did the Roman civilization spread throughout the world through the movement of people?

Roman civilisation did not spread throughout the world. It spread through the Roman Empire and influenced some peoples who lived near its borders. Most of the world did not have contact with the Romans.

The movement of people was certainly an important factor in the spread of Roman civilisation, though it was not the only one.

A key role in spreading Roman civilisation was the establishment of Roman colonies (settlements) throughout the empire, partly to strengthen Roman control and partly to give land to Roman farmers who did not have enough land and landless Romans. This was a major factor in the latinisation of the empire.

Contact though travel by traders in a flourishing trade and the taking of large number of slaves to Rome were other factors. Being under Roman administration also contributed as the conquered peoples had to deal with Roman officials The emperors also actively promoted the spread of an imperial ideology to justify their rule, bring the conquered people close to Rome and foster a more homogeneous empire.