While ascending the Missouri in 1804, Lewis and Clark met trader Jean Valle, who had wintered in Cheyenne camps near the Black Hills and who recounted extensive horse-raiding upon Spanish settlements. Trail of the Red Butterfly is the first novel to depict such a raid through Cheyenne eyes. Cheyenne Kit Fox headman Stone learns that his twin, Whirlwind, has gone missing on an 1807 foray into northeastern New Spain. Gathering an eclectic party of Cheyenne,...