In the midst of the Mexican-American War (1846-1848), when the border between the United States and Mexico and the sovereign status of New Mexico were being contested, Antonio Trujillo, an American citizen, was a Mexican military official operating north of the Rio Grande River.
In events known as the Taos Revolt, Mexico directed Trujillo to issue orders for Mexicans to take up arms against the United States. When he did, his role became treasonous.
Trujillo was arrested. On March 16, 1847, he was tried for treason in U.S. District Court, found guilty, and sentenced to death.
After the Supreme Court affirmed his conviction and President Polk declined to intervene, Trujillo was hanged in Santa Fe on April 16, 1847.
The Federal Death Penalty Project 