Infidels Abroad: A Novel of Mark Twain & John Singer Sargent in an Alternate California

In 1879 Mark Twain meets the young painter John Singer
Sargent aboard a steamer from the Sandwich Islands to San Francisco. But it is not our San Francisco, our California, or our 1879.
In this universe, everything south of the Russian River is an independent Spanish-speaking country called Alta California. Everything north of the river is Rossland, ruled by Imperial Russia. These powerful states are flush with Sierra gold, while the United States is just a weak neighbor on the other side of the Mississippi.
Mark Twain is supplementing the meager royalties from Tom Sawyer by lecturing on "Our Fellow Savages of the Sandwich Islands." John Singer Sargent tours with him, sketching and painting the sights and trying to get a portrait commission from Twain.
Told in the first person voices of Twain and Sargent, illustrated with their sketches, paintings and photos, this is a tale about friendship, ideology, culture clash, and what it means to be an artist.