One of the headstones in the graveyard bears the name Sergio Leone as a tribute.

Other headstones bear the names of 'Don Siegel (I)' (Eastwood's director on five films, four of which preceded this one), and Brian G. Hutton (director of Where Eagles Dare (1968) and Kelly's Heroes (1970)). Patrick McGilligan's 2002 Eastwood biography quotes the star as saying, "I buried my directors."

Editing of the film was done in a log cabin on the shores of Mono Lake.

Universal Pictures wanted the film to be shot on the studio lot. Instead, Clint Eastwood had a whole town built in the desert near Mono Lake in the California Sierras. Many of the buildings were complete and three-dimensional, so that interiors could be shot on location.

The Bible verse on the wall of the church is Isaiah 53:3-4 which reads, "He is despised and rejected of men; a man of sorrows, and acquainted with grief: and we hid as it were our faces from him; he was despised and we esteemed him not. Surely he hath borne our griefs, and carried our sorrows: yet we did esteem him stricken, smitten of God, and afflicted".

Shortly after the film's release, Clint Eastwood wrote to John Wayne, suggesting that they make a western together. Wayne sent back an angry letter in reply, in which he denounced this film for its violence and revisionist portrayal of the Old West. Eastwood did not bother to answer his criticisms, and consequently they did not work together.

Continuity

When the Stranger is first sipping his beer at the saloon, the bottle of whiskey is placed on the bar to the left of his glass of beer. When he reaches for his beer while saying the line "Faster than you'll ever live to be" to the one gunfighter, the bottle of whiskey "jumps" to the right of his glass of beer so he can pretend to draw his gun yet reach for the bottle of whiskey instead.

When the wounded Morg Allen rides into the camp of the three bad guys, he starts to dismount twice in consecutive shots.

On a porch outside a saloon Clint is hold half a glass of beer, threatens a man behind him, lifts his glass which is now full. Has a couple of mouthfuls , shows his prowess with the gun, lifts his glass and it's full again.

As The Stranger arrives in town the Saloon is clearly lit from the front (the word "Saloon" is shadowed on the window shade). After tying up his horse, the stranger walks to the saloon which is now in shadow.

The morning after his first night in Lago the stranger steps out of the hotel and the mayor says "good morning." The shadows on the ground clearly show that it is late afternoon as Lago is located on the western shore of Mono Lake.



Factual errors

When the town men are in the church debating their predicament, there is a plaque on the wall that quotes a scripture. Isaiah 53:3-4 is the scripture address written at the bottom of the plaque, but the scripture written out on the plaque is only Isaiah 53:3 (kjv); verse 4 is missing.



Incorrectly regarded as goofs

When Stacey, Cole and Dan come across three campers in the mountains, they have plenty of ammo despite their guns being given back to them empty when they left prison. However, it can be seen that their gun-belts still had ammunition in them.



Revealing mistakes

When the next to last bad guy is hanged with a bull whip, as he is first hoisted he spins a little and you can clearly see that is is a rope around his neck (not a bull whip), and that it is tied in a knot with some other ropes going down the back of his shirt (obviously attached to a supporting harness).

During the initial ambush practice when they are shooting at the dummies the bullet that breaks the glass in the door as it is opened clearly comes from inside the building.



Miscellaneous

On Duncan's gravestone, the word "marshal" is spelled with one L. In the closing credits, it is spelled with two L.

At the 26 minute mark, Callie attempts to shoot The Stranger while he's taking a bath. The Stranger ducks under water, and while the Sheriff is struggling to subdue Callie they bump into the tub which visibly moves, even though it is full of water with a grown man sitting in it. That would be far too much weight for it to move at all, yet it moves again when they bump into it again a short time later.

When Cole Carlin is chasing after the last of the three campers, he jumps over a log and fires a shot into the ground rather than aiming at the camper.



Anachronisms

When The Stranger gives the Indian children the jars of candy in the general store, the jars have white plastic seals. Plastic was unknown in the 19th century.

When the stranger rides into town, huge tire tracks like those made by a truck are seen on the road.

All houses in the city (Lago) have modern window glass of the type float glass and not "handmade" as they were until the mid-19th century.

Mordecai wears crossed bandoliers filled with .45-70 rifle rounds. Close up shots show these to be loaded with Jacketed Soft Point bullets, which were not available until the 20th century.

After the town has been painted red, a shot pans past the bell tower atop the church. The (lack of) application of paint on the bell tower edges shows it was painted with a spray gun. Also, many of the buildings have a very thin and even coating of red paint applied. Again, obviously done with a spray gun. This technology would not have been available at the time.



Audio/visual unsynchronized

In the scene where the stranger is taking a bath and the woman comes in to shoot him, there is an extra gun shot after the sheriff wraps her up in his arms.



Crew or equipment visible

The last person is shot at the barber shop, you can see the outline of knee pads on the stuntman.

Regarding one of the three bad guys who confront the Stranger in the barber shop. The tall guy with the beard who is shot and crashes through the window into the street. As he attempts to support himself against the hitching post one can clearly see the shape of an elbow protector for his left arm under his shirt.

When the bad guys return to town for the final showdown, one of the bad guys on horseback knocks one of the townspeople over a table in the street. As the table is tipped over you can clearly see a moving blanket under the table cloth there to protect the stuntman.



Character error

Sheriff Shaw, in talking with The Stranger as he's taking a bath, identifies the three men that The Stranger shot in the barber shop as Billy Borders, Ike Sharpe and Fred Morris. Per the cast listing and photo identification, the three characters' names that The Stranger shot in the barber shop are actually Bill Borders, Tommy Morris and Fred Short.

One of the three gunfighters at the beginning says, "Flea-bitten range bums don't usually stop by Lago," pronouncing it "Lay-go". "Lago" is Spanish for lake, and it is pronounced as all the other characters do, "Lah-go".