The name given to the social body formed by the oppressed classes of bourgeois society when it is effectively led by the petty bourgeoisie.
The new owning classes of the end of the feudal regime, which accumulate economic power based on private property instead of on the monopoly of political force, are organized as a political body opposed to the absolutist power of the Ancien Régime. In England, they formed the "Civil Society" in the 17th century under the leadership of the bourgeois landowning nobility and in France -inspired by the English model- the "Third State" in the 18th century, directly under the leadership of the bourgeoisie. They constitute themselves as a nation and as such claim power over the state from the clergy and the nobility. The nation shifts from recognizing the Sovereign to demanding "sovereignty" for itself.
In the development of the national and democratic tasks of the bourgeois revolution, it will not be long before frictions and conflicts arise between the bourgeoisie itself -given to agreeing on smooth transitions with the hitherto dominant classes- and the petty bourgeoisie. The latter, afraid of the consequences of accumulation for its own situation -the perspective of proletarianization- will denounce the bourgeoisie as a new "money aristocracy", reviving the utopia of the egalitarianism of "civil society", the undifferentiated magma of the "oppressed classes", at a time when artisans are still the largest segment of the proletariat.
The "people" is then born, as the supposed subject of political life within the bourgeois system and the materialization of the bourgeois programme, not in opposition to it but, as it could not be otherwise, as a radicalization of the programme actually carried out by the bourgeoisie. That is why the people will become, almost immediately, the point of development of nationalism: reinforcement of the bourgeois state and the market that at the same time demands an impossible leading role in the "sovereignty" that would protect the intermediate classes from the advance of capitalist accumulation.
In its desire to develop its own organizational spaces in the bourgeois state, the petty bourgeoisie will find common ground with the proletariat in the first bourgeois revolutions, precisely because the proletariat is aware that the clearer and more radical the triumph of the bourgeoisie against the feudal classes, the sooner the moment will come for its own open confrontation with the bourgeoisie.
In Germany the decisive struggle between the bourgeoisie and the absolutist monarchy is still ahead of us. But since the Communists cannot count on a decisive struggle with the bourgeoisie before it comes to power, it is in the interests of the Communists to help it to conquer domination as soon as possible, in order to overthrow it in turn as soon as possible. Therefore, in the struggle of the liberal bourgeoisie against [absolutist] governments, the Communists must always be on the side of the former, while being careful to avoid the self-deception of the bourgeoisie and not relying on the seductive claims of the latter about the beneficial consequences which, according to it, the victory of the bourgeoisie will bring to the proletariat. The only advantages that the victory of the bourgeoisie will bring to the communists will be: 1) various concessions that will ease the defense, discussion and propagation of its principles by the communists and, therefore, will ease the cohesion of the proletariat in an organized class, closely united and ready to fight, and 2) the assurance that the day when absolutist governments fall, the time will come for the struggle between the bourgeoisie and the proletariat. From that day on, the policy of the party of communists will be the same here as in the countries where the bourgeoisie already dominates.
Frederick Engels. Principles of Communism, 1847