Maximilian, (1832–1867), emperor of Mexico, 1864–67. Maximilian was established as emperor with French military support. Although he intended to rule in the interests of the people, almost all Mexicans regarded him as a foreign usurper.

Maximilian's full name was Ferdinand Maximilian Joseph. He was the younger brother of Emperor Francis Joseph I of Austria, and his title was archduke of Austria. Maximilian became commander of the Austrian navy in 1854 and was governor general of the kingdom of Lombardy-Venetia, 1857–59.

In 1862 France, Spain, and Great Britain sent troops to Mexico to force payment of Mexico's debts. Spain and Great Britain soon withdrew, but Napoleon III of France kept troops in Mexico in order to create a French-controlled puppet state. French troops drove Mexican president Benito Juárez from the capital in 1863. They then set up a provisional government consisting of Mexican conservatives, who, at Napoleon's urging, declared Mexico a monarchy and offered Maximilian the throne. He accepted and arrived in Mexico with his wife, Carlota (1840–1927), in 1864. Maximilian soon found that he was totally dependent on Napoleon for financial and military aid. Mexican liberals opposed him from the beginning, and he alienated the Roman Catholic church by refusing to return to it lands that had been confiscated during Juárez's rule.

In 1865 the United States demanded the withdrawal of the French forces, and threatened military action unless Napoleon complied. Carlota traveled to Europe to beg Napoleon not to remove the troops, but to no avail. The last French troops left Mexico in March, 1867. Maximilian, believing he could retain power, remained. On May 15 he was captured by Juárez's troops at Querétaro. He was court-martialed, convicted, and executed by firing squad.

Carlota became permanently insane after Napoleon refused to continue aid to her husband, and she never returned to Mexico.