Carl Hermión was a member of the elder branch of the Hermión family who ruled as President of New Granada in the first part of the twentieth century. He succeeded to the presidency in 1906 after the death of his father, Victoriano Hermión.
In March 1922, Mexican President Emiliano Calles proposed that New Granada, along with other areas conquered by Hermión's uncle Benito Hermión in the late nineteenth century, hold a plebiscite on becoming a state of the United States of Mexico. Calles' proposal was opposed by Douglas Benedict, the President of the Mexican business behemoth Kramer Associates. Whether due to Benedict's opposition, or for his own reasons, Carl Hermión rejected Calles' proposal out of hand, and no plebiscite was held in New Granada.
In For All Nails the New Granadan branch of the Hermión family is overthrown in 1973.