The Lex Oppia was a law established in ancient Rome in 215 BC, at the height of the Second Punic War during the days of national catastrophe after the Battle of Cannae.
Instituted by Gaius Oppius, a tribune of the plebs during the consulship of Quintus Fabius Maximus Verrucosus and Tiberius Sempronius Gracchus, the Lex Oppia was the first of a series of sumptuary laws, and it restricted not only a woman's wealth, but also her display of wealth. Specifically, it forbade any woman to possess more than half an ounce of gold, to wear a multi-colored garment (particularly those trimmed in purple), or to ride in an animal-drawn vehicle in the city or any town or within a mile thereof, except in the case of public religious festivals.
The Lex Oppia had been primarily an economic measure in response to serious financial issues during the Second Punic War. However, the restrictions it imposed laid the framework for later sumptuary legislation designed to control expenditure on extravagance for social rather than economic reasons. Notable sumptuary legislation passed after the Lex Oppia's creation includes the Lex Fannia of 161 BC and the Lex Didia of 143 BC. The Lex Fannia was a statute that limited dinner expenditure, the kind of food that could be offered and the number of guests, while the Lex Didia was an application of the Lex Fannia to the entire Italian peninsula that imposed sanctions on providers of, as well as guests at, illegal dinners.
The basis for concern about luxury and extravagance was mixed. It was a universal assumption that indulgence in luxury could undermine traditional military virtues. Also, a devotion to luxury was considered to be a stimulus to greed, and thus a major contributor to the increase in corruption. Finally, there was a widespread tendency to correlate lavish and self-indulgent expenditures with uneconomical use of personal or family fortunes.
Following the Second Punic War, with Rome victorious over Carthage, wealth from the conquered areas began to flow into the hands of the Roman ruling class, transforming their lives from one of traditional agrarian simplicity to ostentatious display and unbounded extravagance. The victory made wealthier Romans aware of the possibilities of different, more comfortable life styles, and gave them access to more varied, more exotic and more luxurious products. During this period, there was an inevitable change of mores, which in practice meant largely the conduct of individuals in the upper strata of Roman society; and with the financial woes eliminated, there was no longer a reason for women to restrict their expenditures. With Rome rich in Carthaginian wealth, attempts to check self-indulgent expenditure with sumptuary legislation proved vain. Consequently, two tribunes of the plebs, Marcus Fundanius and Lucius Valerius, proposed repealing the Lex Oppia.