Think about ancient Britain. Many people believe Britain was completely Roman. In big cities like London, which Romans called Londinium, the rich elite loved Roman life. But did everyone in Britain live like Romans? No, most people did not.
Life in the countryside was very different. While the rich enjoyed warm baths in the city, rural families lived in simple homes. They were isolated from the big trade routes of the Mediterranean Sea. These people did not speak Latin; instead, they spoke their own Celtic dialect. They did not care about the Roman emperor. Their connection to Rome was purely transactional, which means they only cooperated when they got money or safety. They did not want to flourish under Roman rules. Sometimes, they would rebel against Roman tax collectors. When local battles started, they did not fight for Rome. Instead, they followed a local warlord who promised to protect them. They wanted patronage, which means they wanted help and rewards from local leaders, not from a far-away empire. They were never truly loyal to Rome.
In the end, Rome left Britain, and the Roman way of life quickly disappeared. If you visit Britain today, you can see old Roman walls, but the local people never truly changed. They stayed Celtic at heart.