A contio was a non-decision-making meeting called by a magistrate or priest with ius contionandi. Within these very broad terms the institution appears to have been relatively flexible. Thus, contiones could be purely informative, communicating important news to the people, for example military events, Livy 10.45.1; or emergencies, as happened in 184, when the consul gave his famous address warning the people about the Bacchanalian conspiracy, Livy 39.15–6. Some contiones had an official function in presenting new legislation, which had to be put before the people at least three market days before it could be voted on. These legislative assemblies were themselves preceded by a special contio, where the so-called suasio/dissuasio took place. This was a formal debate on the proposal held immediately before the vote was taken in the assembly. The two meetings were therefore intimately linked and their attendance virtually identical. These contiones must be distinguished from those called ad hoc by a magistrate or priests, wishing to address the people on any topic. It is the latter type which is our main concern in this chapter.

The contio provided the only official setting for political leaders to meet the people, and the picture presented by the ancient sources is one of lively civic events, which played a significant part in the political life of the republic.