The Gladiators
(First edition: London: Jonathan Cape 1939)

The Gladiators was Koestler's first published novel, an historical novel set in the ancient Rome and narrating the revolt of Spartacus, a slave gladiator that escaped, succeeded in collecting several thousands of fellows and building up an independent State in the South of Italy that was able to survive for a few years. Apart from the historical character of Spartacus, that Koestler studied at length, the book was largely inspired by the reflections that he was carrying on about the ethics of a revolution, thoughts that lead in the very same period to Koestler quitting the Communist Party and publishing, a couple of years later, to the publishing of his most famous novel, Darkness at Noon.

The Gladiators, Darkness at Noon, and Arrival and Departure were later described by Koestler as a trilogy about the conflict between ends and means, specifically in politics.