Isaac Asimov’s novel, published in 1952, belongs to the series about the Galactic Empire, which also includes the books “Stars Like Dust” and “A Pebble in the Sky.”
The plot takes place during the time when Trantor is transitioning from a regional power into a state that controls the entire Galaxy. By then, Trantor controls half of the inhabited worlds.
The independent planet Sark exploits the planet Florina, earning by means of “kyrt”—a universal fiber that can be grown only on this planet. Attempts to break Sark’s monopoly by planting kyrt elsewhere were unsuccessful; instead, only cotton grew. The five-hundred-million population of the planet, under inhuman conditions, produces kyrt under the supervision of trained co-nationals (“residents”) for tens of thousands of Sark’s inhabitants (“patrols” and “squires”). At the same time, Trantor, to strengthen its own power, is not opposed to annexing these two worlds.