The Revolt of the Ciompi broken down to its simplest form, is a revolt of social mobility and unfairness for certain classes of Florentine citizens.
To better understand the event, it is best to first analyze the players involved:
The Ciompi (The Wool Carders): lower-class laborers of the Florentine commune concerned with being able to influence the politics along with other lower-class laborers.
il popolo grosso (the fat people): upper-class Florentine citizens involved in trade, banking, physicians, pharmacists, etc. They were members of the most prestigious guilds in Florence.
Signoria of Florence: Government body made up of 9 members (priori) who were chosen from the guilds.
The Ciompi, being wool carders, felt ignored considering that they were part of the textile industry and yet had no representation with any guild (even though there was other textile-related guilds of various classes.) Their complaints ranged from the wages received by the lower-class to production caps. Despite their lower-class background, the Ciompi and other laborers, were not uneducated. Many left accounting books and Florentine state papers found in the modern day archive of the city, calculate that about 80% of the children knew how to read at the time of the revolt.
In the summer of 1378, the Ciompi presented a list of petitions to the Signoria, including a request o have a voice in the fiscal policies of the city. After little to no response, in July 22nd, the Ciompi stormed il palazzo della signoria (the governmental palace) and seized power. Michele di Lando, a fellow wool carder, was placed in a position of power. Despite the small success, the Ciompi did not get far and in a matter of time were attacked by not just il popolo grosso but also other lower-class laborers. The ciompi and the rest of the lower-class suffered from various disagreements regarding funds. They were rather desperate and the rule of di Lando lasted very little time.
So what is important to take away from the revolt? it is easy to look at this without 21st century perspective as a form of socialist revolt. Samuel Cohn describes the Ciompi in the best possible way:
"It is not necessary to consider the Ciompi a fully developed socialist movement; they clearly did not have an ideology or plan of action that can be compared to late nineteenth-century working class movements. But the abscence of such expressions and actions does not signify the opposite- a sub-political population."
The Ciompi are best seen as a social class desperate for mobility and reacting to the world around them. They saw the government body as unfair and biased towards the upper class guilds and demanded to be represented equally (afterall, they were paying taxes as well.) Ultimately, the lack of a common objective proved to be the downfall of the Ciompi. Laborers and merchants alike did not trust the Ciompi established government. It was only a short time until il popolo grosso returned to its position of power.
Recommended readings:
The Laboring Classes in Renaissance Florence By Samuel Kline Cohn
Florentine Histories by Niccolo Machiavelli. Primary source, a little bias, good at displaying the attitudes of the upper class when looking back at the revolt.