What the cloaca seems to imply, we find conveyed in express terms in the treaty with Carthage. As this treaty was concluded in the very first year of the commonwealth, the state of things to which it refers must clearly be that of the latest period of the monarchy. It appears then that the whole coast of Latium was at this time subject to the Roman dominion: Ardea, Antium, Circeii, and Tarracina, are expressly mentioned as the subject allies (ὑπήκοοι) of Rome. Of these, Circeii is said in the common story to have been a Roman colony founded by the last Tarquinius; but we read of it no less than of the others as independent, and making peace or war with Rome, during the commonwealth down to a much later period. Now it is scarcely conceivable that the Romans could thus have been masters of the whole coast of Latium, without some corresponding dominion in the interior; and we may well believe that Rome was at this time the acknowledged head of the Latin cities, and exercised a power over them more resembling the sovereignty of Athens over her allies than the moderate supremacy of Lacedæmon. On the right bank of the Tiber the Romans seem to have possessed nothing on the coast; but the stories of Etruscan conquests which we find in the common accounts of Servius Tullius, are so far justified by better testimony as to make it probable that in the direction of Veii the Roman dominion had reached beyond the Tiber, and that the territory thus gained from the Etruscans formed a very considerable part of the whole territory of Rome. It is well known that the number of local tribes established by the later kings was thirty; whereas a few years after the beginning of the commonwealth we find them reduced to twenty. Now, as even the common account of the war with Porsenna describes the Romans as giving up to the Veientines a portion of territory formerly conquered from them, it becomes a very probable conjecture that the Etruscans, soon after the expulsion of the kings, recovered all the country which the kings had taken from them; and that this was so considerable in extent, that by its loss the actual territory of the Roman people was reduced by one-third from what it had been before.