The title character, Diederich Hessling, a dedicated 'Untertan' in the sense of a person subservient to a monarch or prince, is an immoral man who is meant to serve as an allegory of both the reign of Kaiser Wilhelm II and German society of his time.

The novel was completed during the July Crisis in 1914, shortly before the outbreak of World War I. Extracts had been published in the satirical magazine Simplicissimus from 1912 onwards, causing great controversy.

Throughout the novel, Hessling's inflexible ideals are often contradicted by his actions: he preaches bravery but is a coward; he is the strongest militarist but seeks to be excused from conscription; his greatest political opponents are the Marxist Social Democratic Party of Germany (SPD), yet he uses his influence to help get his hometown's SPD candidate to the Reichstag parliament, in order to defeat his liberal business competitors; he starts vicious rumors against the latter and then dissociates himself from them; he both preaches and enforces Christian morality against others but lies, cheats, and regularly commits adultery.

When the novel was fully published in German in 1918, it immediately sold nearly 100,000 copies — the success that Heinrich Mann never achieved again in his entire life, while the author was denounced as a traitor to his country[3] for his "unpatriotic" or even "Communist" stance; at the same time, some reviewers described it as an "account of a gullible people seduced by power".

[1] Among the problems of the artistic structure of the novel that are often "obscured" by its "evaluations of the political dimensions" Karin V. Gunnemann noted "inconsistencies in the plot" and "confusing labyrynth of intrigues and the exaggerated descriptions of facts" which Mann uses as "elements of the world he wishes to depict",[2] which, however, may be viewed as "a device to reach a unity of form with content", praised by Mark Roche as "an aesthetic corollary of Hessling's self-contradictory concepts of justice.

Like other German novels of the era, such as Theodor Fontane's Effi Briest, or even his brother Thomas Mann's Buddenbrooks, the principal target is the hypocrisy of the middle class and the risk of social collapse in a nation of loyal 'Untertan' citizens.

[1] The novel introduces modern psychological insights and reveals Hessling's sado-masochism in such episodes as him decorating the headmaster's cane and satisfaction when being punished, up to the climax of facing the Kaiser's "power which transcends us and whose hoofs we kiss.

In East Germany, the book was made into the 1951 DEFA film Der Untertan (released in English as The Kaiser's Lackey), directed by Wolfgang Staudte and starring Werner Peters as Diederich Hessling.