Journey to the End of the Night by Louis-Ferdinand Céline (1932)

Ferdinand Bardamu signs up for the war on a whim, chasing a passing band down a Paris boulevard, and by nightfall he is loose in a France gone mad with slaughter, having learned the one thing he will carry everywhere after: that he is a coward, and that cowardice may be the only sane answer to a world bent on killing him. From the trenches he flees, to a fever-rotted African colony, to the clanging assembly lines of Ford's Detroit, to a tubercular Paris slum where he hangs out a doctor's shingle among people too poor to be saved. Céline wrote it in a French nobody had dared set on the page, the gutter slang and broken rhythms and trailing ellipses of real speech, and made every polished sentence before him sound embalmed. This is the great novel of looking straight at the worst of us and refusing to flinch, of seeing that we are all traveling the same road into the same dark. Few books are this funny about despair, or this tender toward the ruined.