Symbolism of the Mexican flag: colours, eagle and coat of arms

The flag of Mexico brings together symbols from very different eras on a single cloth. According to the National Institute for Historical Studies of the Revolutions of Mexico (INEHRM), it mixes allegories from three civilisations: the pre-Hispanic, with the eagle on the cactus; the Spanish, religious and colonial, with the oak and laurel branches; and that of Enlightenment liberalism, French and English, with its green, white and red colours. This guide explains each element and what the law says about it.

The eagle, the cactus and the serpent

Article 2 of the Law on the National Arms, Flag and Anthem describes the coat of arms precisely: a Mexican eagle with its left profile showing, its wings slightly spread in a fighting stance, perched with its left talon on a flowering nopal cactus growing from a rock that rises out of a lake, and holding with its right talon and its beak, as if to devour it, a curved serpent.

According to the INEHRM, the eagle standing on a cactus is the mythical founding symbol of Olmec, Maya and Mexica mythology, which became the emblem of the Mexica state and, in time, the national coat of arms. The rock in the lake recalls the island where, according to tradition, the Mexica founded México-Tenochtitlan. The insurgent leader José María Morelos was the first to use the eagle on the cactus as a coat of arms on a flag, in 1812, according to the same institute.

The oak and the laurel

Under article 2, two branches, one of oak in front of the eagle and one of laurel on the opposite side, form a lower semicircle and are joined by a ribbon of three stripes which, in natural colours, match those of the flag. The INEHRM attributes them to the Spanish tradition and describes them as symbols of strength and victory; they were introduced by the 1823 decree that set the coat of arms of the first Republic.

The colours

The law describes the colours, green, white and red from the pole, but gives them no meaning. They go back to the flag of the Trigarante Army, made after the proclamation of the Plan of Iguala in 1821: according to the INEHRM, on it white stood for religion, green for independence and red for union, the three guarantees of Agustín de Iturbide’s army. The current law does not adopt that or any other interpretation of the colours.

The coat of arms as a protected symbol

The coat of arms is protected by law. Under article 5, every reproduction corresponds faithfully to the official model, which cannot be varied or altered. Authorities use it without authorisation; institutions and individuals need the authorisation of the Ministry of the Interior (article 6). On the authorities’ coins, seals, stationery, buildings, vehicles and websites, only the words «Estados Unidos Mexicanos» may be inscribed alongside it, in an upper semicircle.

A model of the coat of arms authenticated by the three branches of government is kept at the General Archive of the Nation, another at the National Museum of History and another at the Mint (article 2).

The reverse of the flag

Since the 1995 amendment, article 2 provides that when the coat of arms is reproduced on the reverse of the flag, the eagle stands on its right talon, holding the serpent with its left talon and beak. Seen from either side, the eagle thus faces the pole.

The coat of arms and the stripes

The coat of arms sits in the centre of the white stripe, with a diameter of three quarters of its width (article 3). The guide to flag sizes shows how these proportions are calculated, and the guide to the history of the Mexican flag traces the earlier designs, from Hidalgo’s banner to the 1968 design.