Anachronisms: In the first scene (dated 1792), it is stated that prints of Goya's anti-inquisition paintings are sold "even as far as Mexico". The use of the name "Mexico" is incorrect here, since at the time, it was actually a Spanish colony, not a country, and was known as "The New Spain". It was not until 1810 that the colony began fighting for its independence (on sept. 16th) in a war that lasted until 1821. Then it was known as "The Empire of Mexico" with Agustin De Iturbide as its emperor and included not only its present day territory but also the southern US states of Arizona, New Mexico, California and Texas among others, as well as the central American territories which later became Guatemala, Belice, Honduras, Nicaragua, El Salvador and Costa Rica. Later, in 1824 Iturbide was executed, the Central American territories became independent, and the first Mexican constitution was issued which established a republic as the form of government and for the first time used "Estados Unidos Mexicanos" (United Mexican States), or in short form Mexico, as the official country name. It was also at this time that the green, white and red flag with an eagle in the center was adopted (though the eagle was different from the present-day eagle on the country's flag).
Factual errors: The movie was inspired by Goya's Milkmaid of Bordeaux painting (Portman being cast because she looked like the girl in the painting). However, the movie depicts Milkmaid of Bordeaux as being painted in 1792 (the time when Ines was arrested) while in reality it is dated 1825-1827 and Goya's authorship of it has been doubted.