original: they had extensive maritime trade contacts with the roman empire .
simplifications: they had extensive maritime trade contacts with the roman empire . they had large maritime trade contacts with the roman empire . they had many trade relationships with the roman empire . they had extensive sea trade contacts with roman empire . they traded with the roman empire . they had extensive maritime trade contacts with the roman empire . they had large sea trades with the roman empire . they had a lot of naval trade contacts with the roman empire .