Patricians and Plebeians
In Roman history the distinction between patricians and plebeians is first noted in the period following the expulsion of the kings (i.e. the 5th century B.C.). The word patrician comes from pater, father, the Roman Senate being known as patres. The patricians therefore were the clan which monopolized membership of the Senate whilst the plebeians formed the rest of the citizen body of Rome. The two clans were not racially different, and the origin of the division is difficult to conjecture. Perhaps the patricians had accumulated possession of most of the land, like the Eupatrids in Athens and the Spartiates at Sparta.
The struggle of the plebs to gain political equality is known as the 'Struggle of the Orders'. The chief landmarks in this conflict were: the creation of the office of Tribune and the popular assembly in 493 B.C.; the publication of the law in 451 B.C.; concession of the right of intermarriage between patricians and plebeians, in 445 B.C.; admission of plebeians to the quaestorship (421 B.C.), consulship (366 B.C.), dictatorship (356 B.C.), censorship (351 B.C.), and praetorship (337 B.C.). Finally in 287 B.C. it was recognized that formal decisions of the plebs (plebiscita) were legally binding on the whole body of the citizens, including patricians. In theory the popular assembly became the sovereign body in Rome; in practice the Senate, now open to plebeians, retained control of affairs.
The plebeians were able to extort all these concessions because they formed the backbone of the army, and because they organized themselves, as a state within the state, to take advantage of the power which their principal weapon, the threat of secession, gave them. During the 3rd century, the distinction between plebeians and patricians became less important, though patricians continued to take pride in their distinguished ancestry. Plebeians could assume the traditionally patrician magistracies, but patricians were not allowed to become tribunes, unless they were adopted into a plebeian family. Thus Clodius, the violent tribune of the late republic, was born a member of the patrician gens Claudia.
Alongside the decline in political importance of the patricians went a decline in their number. There are about 50 patrician gentes known in the 5th century B.C., 22 in 367 B.C., and 14 by the end of the republic. Most of these had died out by the time of Vespasian. Constantine reintroduced the title 'patrician' as a mark of distinction for loyal service.