It was published in 1893–1894 by Century Magazine in seven installments, and is a detective story with some racial themes. The plot of this novel is a detective story, in which a series of identities — the judge's murderer, Tom, Chambers — must be sorted out. This structure highlights the problem of identity and one's ability to determine one's own identity. Broader issues of identity are the central ideas of this novel.
One of Twain’s major goals in this book was to exploit the true nature of Racism at that period. Twain used comic relief as a way to divulge his theme. The purpose of a comic relief is to address his or her opinion in a less serious way, yet persuade the reader into thinking the writers thoughts. Twain’s use of satire is visible throughtout the book. Twain’s use of colloquialism (dialect) and local color as features of Naturalism to convey his theme, is impressive and ahead for his time. (Summary by Wikipedia)