Although Roman coinage soon diverged from Greek conventions, its origins were similar. Rome, founded in the 8th century bc, had no true coinage until the 3rd. Roman historians later attributed coinage unhesitatingly to the much earlier regal period: some derived nummus (“coin”) from Numa Pompilius, by tradition Rome’s second king, and Servius Tullius was credited with silver coinage, as well as with bronze stamped with the device of cattle. Roman historical tradition, however, seriously confused the elements of the true picture. Rough, unworked lumps of bronze (aes rude) were certainly used as a metal currency from the 6th century, if not much earlier, perhaps in rare conjunction with very small quantities of unworked gold and silver, themselves also passing by weight. Simultaneously, standards of value appear to have been expressed in terms of cattle and sheep, as is clear not only from the derivation of pecunia (“money”) from pecus (“cattle,” or “sheep”) but also from the early assessment of fines in oxen and sheep. From this it was falsely concluded that bronze coins marked with the device of cattle existed from the 6th century. In fact, the expression of values in terms of cattle may have lasted, officially, into the 5th century, for it was not until the decemvirs (a legislative commission) codified the law and drew up the Twelve Tables(451–449 bc) that fines were fixed in bronze. This bronze still consisted of unworked lumps or, at most, rough bars of irregular weight.

During the 4th century bc, Roman contact with the Greek cities of southern Italy slowly increased; these included such prolific mint cities as Nola, Hyria, and Naples. The coinages of these cities consisted of silver didrachms, of which Rome presumably made use in any necessary dealings with them. A hint is given, however, of widening Roman monetary interests by two issues of bronze token coinage. These, though certainly not produced at Rome, may perhaps be regarded as the earliest coins in the name of the Romans, struck at Naples about 325–285 within the terms of their alliance and intended for use in Campania, as distinct from Rome and Latium. It is unlikely, indeed, that a mint in the proper sense existed at Rome before 289, the year to which Pomponius assigned the establishment of tresviri (a board of three officials) who should be aeris flatores (“bronze melters”); and this mint (in the temple of Juno Moneta) did not yet produce true coins but aes signatum, bronze bars (of about six pounds) lacking a mark of value but bearing on each side a clearly recognizable type (including cattle) and perhaps equivalent in value to a Greek silver didrachm.

These aes signatum bars were halfway between aes rude and true coinage. In 269 true coinage appeared. It consisted of aes grave, large circular cast coins of bronze all bearing marks of value, from the as (weighing one pound) down to its 12th, the uncia; the obverses showed the head of a deity, the reverses a ship’s prow. These were paralleled at mints elsewhere by similar cast coins; their types showed not, as at Rome, Latin deities but rather Greek (in the south) or Umbrian and Oscan. At the same time, there appeared struck silver didrachms, on the standard of the Greek silver coins of Campania, bearing Greek types but marked ROMANO or ROMA. Accompanied by small struck bronze token coins, these were issued from Campanian mints, and they probably continued to the Second Punic War, terminating in a new issue of silver coins of Roman style and types (marked ROMA), including Jupiter in a quadriga (four-horse chariot) from which their name, quadrigati, derived; they were imitated in electrum by the Carthaginians in Capua. The quadrigati were of the weight of the lighter Romano-Campanian didrachms and reflected the rising cost of silver at a time of stress; concurrently the cast bronze coinage of Rome dropped steadily in weight from an as of one pound to one of three ounces or less. Financial stress is similarly to be seen in the exceptional issue of gold units and halves. Toward the end of the Second Punic War the quadrigati were replaced by silver coins of half their weight, with a Victory on the reverse, and hence called victoriates. By about 190 a mainly silver coinage, Latin-inscribed, was in production at Rome and other authorized mints, accompanied by bronze coinage so greatly reduced in standard (and thus size) that it could at last be struck instead of being cast.

Adjustment of the previously fluctuating relationship between bronze and silver was first secured by the issue about 211 bc of the silver denarius (marked X—i.e., 10 bronze asses), together with fractional coins, also of silver (marked V—i.e., five; and IIS—i.e., 2 1 2 asses—a sesterce, or sestertius). The denarii were lighter than the quadrigati; their types were a Roma head on the obverse, with the Dioscuri (the twin deities Castor and Pollux) and ROMA on the reverse. Their production came to be confined principally to the mint of Rome. The victoriates, again lighter (their weight standard had come from Illyria), were issued until about 150 bc, being perhaps intended for principal circulation outside Italy. The denarius, however, quickly established itself as the major currency in the central and western Mediterranean. In its eastward expansion, Rome learned to make use of local currencies—gold staters of Macedonia and silver tetradrachms of Athens or Asia. Rome was also prepared to employ Macedonian gold in the west, as was shown by the release to western markets of large quantities of gold staters after about 150 bc. In the 2nd century bc, Roman coinage in gold was exceptional. Coinage in bronze, however, continued, but further variation in silver–bronze values was seen in two developments. The as dropped in weight to that of an uncia and then less, becoming a token currency; together with its fractions, it was now always struck and not cast. The value of the denarius in terms of bronze was altered, being revalued about 133 at 16 instead of 10 asses; the silver quinarius (now of eight asses and with the types of the victoriate) became rare; and the silver sesterce (now equal to four asses) virtually disappeared. After about 80 bc the striking of bronze was discontinued until the time of Caesar.

These developments mirrored the economic difficulties of the day. Reduction of the weight of the as from one to 1 2 ounce in 89 bc was accompanied temporarily by debasement of the denarius, resulting in the issue of denarii with serrated edges, intended to show that they were not plated (see plating).