Birth of Our Power is an epic novel set in Spain, France, and Russia during the heady revolutionary years 1917-1919. Serge's tale begins in the spring of 1917, the third year of mass slaughter in the blood-and-rain-soaked trenches of World War I. When the flames of revolution suddenly erupt in Russia and Spain, Europe is "burning at both ends." Although the Spanish uprising eventually fizzles, in Russia the workers, peasants, and common soldiers are able to take power and hold it.

Serge's "tale of two cities" is constructed from the opposition between Barcelona, the city "we" could not take, and Petrograd, the starving, beleaguered capital of the Russian Revolution besieged by counter-revolutionary Whites. Between the romanticism of radicalized workers awakening to their own power in a sun-drenched Spanish metropolis to the grim reality of workers clinging to power in Russia's dark, frozen revolutionary outpost. From "victory in defeat" to "defeat in victory."

The novel was composed a decade after the revolution in Leningrad, where Serge was living in semicaptivity because of his declared opposition to Stalin's dictatorship over the revolution.