Ancient Greece, especially Athens, provides the best documented early example of mass democracy. With the democratic reforms of the fifth century, populism – the direct mobilization of the masses – becomes an effective path to power. This chapter looks at several examples from fifth- and fourth-century Athens, which demonstrate the use of demagoguery as an efficient, if much derided, alternative to patronage-based politics. Ancient Rome provides a somewhat different context. As a republic, Rome gave the masses a more limited and indirect role in politics. Typically, politics was a purely elite affair. Yet for those elites who found the normal insider path blocked to them, direct appeals to the masses could prove effective. However, given the limited formal role for the plebs in Roman politics, this direct mobilization could often lead to violence.