A revolt of citizens in Toledo, Castile, opposed to the rule of the foreign-born Charles I began when the royal government attempted to unseat radical city councilors.

The Revolt of the Comuneros was an uprising by citizens of Castile against the rule of Charles I and his administration between 1520 and 1521. At its height, the rebels controlled the heart of Castile, ruling the cities of Valladolid, Tordesillas, and Toledo.

Toledo is a city and municipality of Spain, the capital of the province of Toledo and the de jure seat of the government and parliament of the autonomous community of Castilla–La Mancha.

Charles V was Holy Roman Emperor and Archduke of Austria from 1519 to 1556, King of Spain from 1516 to 1556, King of Sicily and Naples from 1516 to 1554, and also Lord of the Netherlands and titular Duke of Burgundy from 1506 to 1555. He was heir to and then head of the rising House of Habsburg. His dominions in Europe included the Holy Roman Empire, extending from Germany to northern Italy with rule over the Austrian hereditary lands and Burgundian Low Countries, and Spain with its possessions of the southern Italian kingdoms of Sicily, Naples, and Sardinia. In the Americas, he oversaw the continuation of Spanish colonization and a short-lived German colonization. The personal union of the European and American territories he ruled was the first collection of realms labelled "the empire on which the sun never sets".