How did they satisfied their need

One word military conquest. The ancient Rome uses their military to gain territory so they have land to grow food and space to make the luxuries items. After the Romans conquered the living land (the place where the Romans know exist) the Romans started exploring. Conquering new land on the way. Once they find silk road and a civilization named China. They trade silk with them a short period of time. But this mean that Romans is a strong civilization, because the distance between Rome to Beijing is 8000 kilometers.