Don Agustín de Iturbide y Green, Prince of Iturbide (2 April 1863, in Mexico City, Mexico – 3 March 1925, in Washington, D.C.) was the grandson of Agustín de Iturbide, the first emperor of independent Mexico, and his consort Empress Ana María. He became the adopted son, along with his cousin Salvador de Itúrbide y de Marzán, of Mexico's only other royal heads of state—Emperor Maximilian I of Mexico and Empress Carlota of Mexico. After the death of Maximilian he became Head of the Imperial House of Mexico, but had no children. His claims passed to the daughter of his cousin, Salvador, Maria Josepha Sophia de Iturbide.

Iturbide was the son of Emperor Agustin I's second son H.H. Prince Don Ángel María de Iturbide y Huarte (2 October 1816 – 21 July 1872) and his American wife Alice Green (ca. 1836 – 1892), daughter of Captain John Nathaniel Green, granddaughter of US Congressman and Revolutionary War Gen. Uriah Forrest and great-granddaughter of George Plater, Governor of Maryland.

Her older sister, Elizabeth Rousby Green, (married name Elizabeth Quesensberry) b. ca. 1825 became a historical footnote when President Lincoln's assassin John Wilkes Booth arrived at her house after crossing the Potomac River on his escape route. Had Booth managed to flee the country, his hope had been to seek asylum in Mexico.

When Maximilian and Carlota ascended the throne of Mexico in 1863 with the support of the French troops of Napoleon III, the new monarchs invited the Iturbide family back to Mexico. As it became clear that Maximilian and Carlota could have no children together, they offered to adopt Iturbide, which was agreed to with enthusiasm by his father and reluctance by his mother. They formally named Iturbide their heir on 13 September 1865, with the title His Highness, Prince de Iturbide.

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