Frontispiece of The Captain of the Gray-Horse Troop (1902) The hero of Garland's novel The Captain of the Gray-Horse Troop (1902) is an enlightened calvary officer who protects reservation Indians against greedy cattlemen and corrupt government officials.

Garland's interest in Native Americans extended beyond their use as fictional material. In April 1902 he inaugurated a series of meetings with President Theodore Roosevelt (who was to become a good friend) and other government officials in an attempt to alter government policy towards the Indian, which was eradicating Indian customs, language, and culture in its effort to assimilate them into white culture. To protect the Indians' rights to their allotments of land, Garland headed a committee charged with standardizing government procedures for naming native Americans, for he wanted to protect the Indians' inheritance rights, and at that time white school teachers were arbitrarily assigning names to Indian children, with no consistency even within families. For the next two years, Garland devoted much of his energy to the project .

For discussion of the project and Garland's role in it, see Daniel F. Littlefield, Jr., and Lonnie E. Underhill, "Renaming the American Indian: 1890-1913," American Studies 12 (Fall 1971): 33-45.