Roman assemblies
The Roman Assemblies were institutions in ancient Rome. They functioned as the machinery of the Roman legislative branch, and thus (theoretically at least) passed all legislation. Since the assemblies operated on the basis of a direct democracy, ordinary citizens, and not elected representatives, would cast all ballots. The assemblies were subject to strong checks on their power by the executive branch and by the Roman Senate. Laws were passed (and magistrates elected) by Curia (in the Curiate Assembly), Tribes (in the Tribal Assembly), and century (in the Centuriate Assembly).
When the city of Rome was founded (traditionally dated at 753 BC), a senate and an assembly, the Curiate Assembly, were both created. The Curiate Assembly was the principal legislative assembly during the era of the Roman Kingdom. While its primary purpose was to elect new kings, it also possessed rudimentary legislative powers. Shortly after the founding of the Roman Republic (traditionally dated to 509 BC), the principal legislative authority shifted to two new assemblies, the Tribal Assembly ("Citizen's Assembly") and the Centuriate Assembly.
Under the empire, the powers that had been held by the assemblies were transferred to the senate. While the assemblies eventually lost their last semblance of political power, citizens continued to gather into them for organizational purposes. Eventually, however, the assemblies were abandoned.