(Italian: “people”), in the communes (city-states) of 13th-century Italy, a pressure group instituted to protect the interests of the commoners (actually, wealthy merchants and businessmen) against the nobility that up to then had exclusively controlled commune governments. It was one of a number of groups competing for power in the commune and in some cities succeeded in dominating the government in the late 13th century.

The popolo was organized either on a territorial basis (by quarters or districts) or on a corporative basis (by guilds); in some cities, notably Florence, a combination of both types developed. It gradually developed its own officials, who paralleled those of the commune. In the mid-13th century the office of capitano del popolo (“captain of the people”) became prominent. This official was charged with leading the military forces of the popolo and ensuring justice to injured members; like the communal officer known as the podestà, he was usually a native of another city. The effective leaders of the popolo were the local representatives, the anziani, or “elders” (sometimes known as priors).

In Florence the organization of the popolo developed early and became quite powerful. From 1250 to 1260 it controlled the government (in the regime known as il primo popolo), and after the seizure of power in 1282 its power was firmly established. By the beginning of the 14th century, its priors, chosen from among guild members, formed the supreme executive of the commune.

In the writings of medieval chroniclers and modern historians, the term popolo grasso (“fat people”) refers to the wealthy middle class of merchants and businessmen that dominated the economic and political life of the Italian communes. The term popolo minuto (“small 【or common】 people”) refers to the lower-middle class of proprietors of small shops and small merchants denied direct participation in government; it is sometimes extended to include the wage-earning proletariat, the most economically deprived group.