Emperor of Mexico (1864–67). Brother of the Austro-Hungarian emperor Franz Josef and Archduke of Austria, Maximilian was established as emperor of Mexico under French auspices in 1864. In 1867, however, Napoleon III was forced to withdraw his support as a result of US pressure, and Maximilian was confronted by a popular uprising led by Benito Juárez. His forces proved unable to resist the rebels and he was captured and executed.