All roman citizens from noble families were members of what class

Roman citizens from noble families were members of the Patrician class.  Roman society was divided into two classes: Patricians and plebeians.  The plebeians made up about 95% of the population; the rest were patricians.  The status of patrician could be earned only through birth; plebeians could not be promoted to the upper class.

Patricians enjoyed greater privileges than plebeians during the life of the Roman Republic, but these distinctions were blurred over time.  Eventually, the benefits offered to patricians were nominal at best, and therefore the status lost most of its significance.  At first, patrician families were almost exclusively rich while plebeians were almost exclusively poor, but over time many patrician families squandered their wealth while many of the wealthier plebeians achieved a standard of living similar to that of the patricians.