The Magnificent Seven Movies: Original Timeline
The four films from 1960-1972 form a loosely connected series centered around the character of Chris Adams, though the connections become increasingly tenuous with each sequel. Yul Brynner returns as Chris Adams in the first sequel, but the character is then recast with George Kennedy and Lee Van Cleef in subsequent films, with each actor bringing their own interpretation to the role.
While the character name provides continuity, each sequel essentially functions as a standalone story with a mostly new supporting cast and fresh mission. The films are more thematically linked than narratively connected, each exploring variations on the concept of assembling a team of skilled fighters to protect the vulnerable against powerful antagonists.
There are 2 other watch orders available - see the links up above.

The Magnificent Seven
Seven gunfighters are hired to protect a Mexican village from bandits terrorizing the local peasants.
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Return of the Seven
When bandits capture most of the men from a Mexican village, the wife of Chico (one of the original Magnificent Seven) seeks help from Chris and Vin. The remaining members recruit new gunfighters to rescue the prisoners and protect the town once again.
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Guns of the Magnificent Seven
A Mexican revolutionary's loyal subordinate hires American mercenary Chris Adams and a team of skilled gunfighters to rescue their imprisoned leader from the forces of President Diaz.
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The Magnificent Seven Ride!
Marshal Chris Adams recruits a writer and five prisoners to help him take down a gang of Mexican bandits after personal tragedy strikes. This is the fourth and final film in the original Magnificent Seven series.
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Other Film Series
American Ninja
A cult martial arts action series from Cannon Films following American soldiers skilled in ninjutsu as they battle various criminal ninja organizations.
Django
A sprawling collection of Spaghetti Westerns featuring the enigmatic gunslinger Django across multiple timelines and interpretations.
James Cameron
Canadian filmmaker known for groundbreaking science fiction and technical innovation, director of the highest-grossing films of all time.
Karl May
German-produced Western films from the 1960s based on Karl May's novels, featuring the friendship between Apache chief Winnetou and German frontiersman Old Shatterhand.
Predator
Elite alien hunters stalk Earth throughout history, seeking the most dangerous prey in brutal combat.
The Crusades
Films depicting the medieval religious wars between Christian and Muslim forces for control of the Holy Land from 1095 to 1291.