The Holdout — Robert J. Steelman

The Civil War is almost over, and up to now, Charlie Calloway has been a deserter, a compulsive gambler, and an irrepressible con man. But he is determined to reform for the love of Lorna, his erstwhile sweetheart, who left him to work with the destitute in San Francisco's Chinatown. Thus begins an odyssey filled with misadventure in which the dodgy cardsharp just barely keeps ahead of the law. When the Union Army dubs him a spy, he hides in their midst and even manages to deal the Confederates a major blow. Later, Charlie toils with the Amish in Pennsylvania, rallies with suffragists in Kansas, and is quite rudely abducted by scalp-hungry Sioux. In San Francisco, he faces the toughest challenge of all in a showdown with Little Pete, the Chinese warlord who's as powerful as he is ruthless...