How would you describe the politics and cultures of some faction?

[artavazd]

Hello there.

I am attempting to create a setting for a role-playing games and I am looking for some short overview of the following cultures:

1. Barbarian culture (Lusotana, Celts, Sweboz, Getai).

2. Romans

3. Hellenic

3. Eastern Nomad cultures

Like if I would be describing the Roman culture then I could speak about the tension between the Plebeians and Patricians, how popular generals could overthrow the government, how all pompous expression of glory and 'for Rome' was merely a tool to increase the landowners power even more, and so forth.

might want to add "Eastern Feudalism", or "Helenic Feudalism" because factions such as Armenia and Pontus do not fit with Eastern Nomad culture (neither were nomadic )