The characteristics of the 19th century American novel differ based upon the period to which is being referred to.
There were three different writing movements which took place during the 19th century: The Romantic Period, The American Renaissance, and The Realist Movement (Realism).
The main characteristics of the Romantic Period (dating 1800-1860) were:
-The theme of the personal journey in regards to independence.
-Romantics wished to move "life" from the corrupt urban areas to those of the nature-filled rural areas.
-Romantics associated this area (the rural) with clarity, purity, and independence.
-The Romantics valued intuition and feeling over reason, the power of imagination, and viewed life as it should be (idyllic), instead of how it really was.
The American Renaissance (1840-1860-note the overlap with Romanticism) was a period which instilled value in what it meant to be American. The Renaissance writers wanted to examine the possibilities associated with human ability while paying special attention to an individual's ego. The American Renaissance writers desperately wanted to define themselves as American, and not British, writers.
The characteristics of this period were/are:
-Rise of feminism.
-Rise of abolitionism.
-Necessities of self-improvement.
Outside of that, the period illuminated the experiencing of life through intuition and not simply relying on the physical world. Therefore, the idea of a Utopian society was of the utmost importance.
The last period of the 19th century was The Realist Movement (1855-1900). This period's writers wished to focus upon societies realism that problems exist within the American culture. The Realists, therefore, focused upon changing specific social problems seen in America at the time. These texts focused more upon a "truer" view of life as it was (as opposed to the idealized views the Romantic and Renaissance writers held). Above all else, the Realists wanted to portray life as it was, and their focus was on the ordinary human being and the trials and tribulations which this individual (or group) faced.