The vast majority of fit young Frenchmen were mobilized, so those artists left behind in Paris were either foreign or too old or unfit for combat. Pablo Picasso, then known as the inventor of Cubism, remained a prominent figure, alongside his fellow Spaniards Juan Gris and María Blanchard, the Mexican Diego Rivera, the Italian Gino Severini, the Lithuanian sculptor Jacques Lipchitz and the French painters Georges Braque, Henri Laurens, Fernand Léger and Henri Matisse.
One focus of this book is the sheer diversity of the work produced by these artists; another is the move made by most of them toward a more structured, architectural Cubism, especially from 1917, which could be taken as reparation against the destructive forces that seemed to have taken over the whole world.