Book excerpt: Here is the definitive biography of Mencken, the most illuminating book ever published about this giant of American letters. We see the prominent role he played in the Scopes Monkey Trial, his long crusade against Prohibition, his fierce battles against press censorship, and his constant exposure of pious frauds and empty uplift. The champion of our tongue in The American Language, Mencken also played a pivotal role in defining the shape of American letters through The Smart Set and The American Mercury, magazines that introduced such writers as James Joyce, F. Scott Fitzgerald, and Langston Hughes.