John Landis said in an Empire magazine piece on the film, that it was taken out of his hands in post-production by the studio (Orion Pictures), and heavily edited. It had its first scene cut for instance.
In his memoir, "Life Itself", film critic Roger Ebert recounted appearing as a guest on The Tonight Show Starring Johnny Carson (1962) alongside Chevy Chase who was promoting the film. During the interview, Ebert was asked what his least favorite film of the holiday season was, he replied ¡Three Amigos!. Chase said "looking forward to your next picture", but later confided with Ebert backstage that he didn't "think it's so hot, either."
Director John Landis has said of the singing turtle: "That singing turtle was my idea. It's a desert setting, so we needed lots of animals. The animals were on-set with handlers and wires, so they didn't run, but I remember the coyote was the most difficult."
Randy Newman, who wrote some of the songs for this movie, was the voice of the singing bush. This was possibly a reference to the burning bush from the Holy Bible's book of Exodus. Moses' (the Amigos') vision to guide the oppressed Hebrews (Santa Pocans) into freedom.
Rebecca Underwood is billed in the credits as "Señorita Kissing Ned". A former Playboy Playmate, she is actually known as Rebecca Ferratti, and had been the Playboy Playmate of the Month for June 1986.
The name of the movie on the billboard, in the scene where the Amigos break into the studio to retrieve their costumes, was the "The Dueling Cavalier". This is also the name of a movie made by Don Lockwood and Lena Lamont in the classic Singin' in the Rain (1952).
Tony Plana turned down Oliver Stone's Platoon (1986) to appear in this. He had also appeared in Stone's Salvador (1986) and knew that shooting Platoon (1986) in the Philippines would be an even more difficult shoot, compared to the 5 star hotel that was being provided for the Tucson location for ¡Three Amigos! (1986). Stone did not talk to him for years.
The amount of money that was offered to the three amigos to come to Santa Poco was one hundred thousand pesos. The Mexican to U.S. dollar exchange rate would have been about a little over two pesos to one dollar in 1920. Adjusting for inflation, in 2014, this would have netted a 2.5 million dollar stipend. In 1986, one hundred thousand Mexican pesos would have netted one thousand dollars before the peso re-valuation during the mid 1990s. In 2014, the Three Amigos' payment would have been about seventy-six dollars.
The name of the movie on the billboard, that starred Miss Rent, was "The Dueling Cavalier". The names of some of the films that the Three Amigos had starred in, either singularly or together, were "Shootin' For Love", "Little Neddy Grab your Gun", "Those Darn Amigos!", "Little Neddy Goes to War", and "Amigos! Amigos! Amigos!".
The name of the small desert town in Mexico was "Santa Poco". The name of the village is spelled and pronounced as "Santa Poco" in the movie and soundtrack. This is grammatically incorrect, as "santa" is a feminine word and "poco" is a masculine word. Since in Spanish the genders should match, the proper spelling would be "Santo Poco", though "San Poco" would actually be the correct form used in Mexican Spanish, due to other conventional rules regarding the letters with which a name begins.
The Video & DVD Guide said this film was a "send-up of The Cowboy Star (1936), while Halliwell's said that it was a "take-off of The Magnificent Seven (1960)". Moreover, Movies on TV & Videocassette said that it was a "spoof of Mexican bandit movies", while Rating the Movies said that the picture was a "spoof of B-westerns". Further, Variety stated that this "film is a takeoff of The Magnificent Seven (1960)" and parodies "the style of a number of other classic westerns."
Carl La Fong (actor and stuntman) is the name used to great comic effect when W.C. Fields is questioned about that character's whereabouts in It's a Gift (1934): Insurance Salesman: "Do you know a man by the name of LaFong? Carl LaFong? Capital L, small a, Capital F, small o, small n, small g. LaFong. Carl LaFong." Harold: "No, I don't know Carl LaFong - capital L, small a, capital F, small o, small n, small g, and if I did know Carl LaFong, I wouldn't admit it!"
The make and model of the German mail aircraft was a red, black, and white, Bücker Bü 131, a 1930s basic training aircraft used during World War II. The movie takes place in 1916, but this aircraft had its first flight on April 27, 1934. The aircraft is called a tubman 601, although there is no real aircraft with that name.
The first character in the movie's title featured an exclamation mark, "!", that was upside down, "¡", which is one of the rarest occurrences for a theatrical feature film title. Yet, in Spanish, it's a normal way to start an exclamatory sentence or phrase. (For example, ¡Ay, Dios mío!)
Despite the notorious financial and critical failure of Heaven's Gate (1980), the Hollywood films industry within about five years of that movie revived the oater movie genre during the mid-80s producing a mini-cycle of Western movies, of which this western spoof was one. In 1985, the dream factory churned out such Western oaters as Silverado (1985), Rustlers' Rhapsody (1985), Pale Rider (1985), and Lust in the Dust (1985). ¡Three Amigos! (1986) followed.
When the Amigos say their chants to summon the Invisible Swordsman, Lucky Day (played by Steve Martin) chants "Farley-Farley-Farley-Farley-Farley-Hfuhruhurr!" This is a reference to the often-hilariously mispronounced name of Dr. Michael Hfuhruhurr, Steve Martin's character in his earlier film "The Man With Two Brains."
In the late 1980s, a trio of top wide receivers, Vance Johnson, Ricky Nattiel, and Mark Jackson, who played for the Denver Broncos, were nicknamed the "Three Amigos" after this film came out. The players were part of a Broncos team that reached three of four Super Bowls between 1986-1989, losing all three times.
The trivia items below may give away important plot points.
The basic story and quite a few scenes borrow heavily from Seven Samurai (1954). The sequences are: A village is terrorized by bandits; a few villagers go into town to find help; they have very little to offer; no help from the town's people; they find "warriors"; they prepare defenses (among them, water filled trenches); a large climactic battle; the leader is the last of the bandits to die; three prepare to leave the village; one looks back at the girl, with whom he fell in love (though ¡Three Amigos! (1986) has a slightly happier version of what happens then).