Gladiator is about the victorious and admired Roman General, Maximus Decimus Meridias. His only desire is to return home from battle to his wife and son. He has been away for over two years. But sadly, things are not that easy for Maximus. The Emperor of Rome, Marcus Aurelius sits on his death bed and tells that he would like Maximus to insure that Rome returns to public rule. This means taking temporary control of the Empire until the Roman Senate can get it together enough to take over. Maximus at first refuses, but ultimately agrees to wield the power when the emperor dies. .
The Emperor then tells his actual son Commodus about how he wishes his empire to be run, and that he would like Maximus to do it. Commodus becomes angry and hurt and then strangles his own father. Then proclaims himself the new Emperor. Maximus refuses to serve under the new emperor which sentences him and his family to death. Maximus kills the guards sent to kill him without struggle but finds he is too late to prevent the death of his wife and son.
Maximus is found in poor condition and taken as a slave for Proximo. Maximus and other slaves are trained to fight as a Gladiators. At first Maximus refuses but eventually learns that he must fight or die. Maximus becomes known as "Spaniard" by the slaves and crowds at the arenas. Because he has been at battle, unlike the others, he becomes an amazing gladiator. He fights his way to fame with new identity. .
Proximo's troupe is called to Rome to participate in a marathon of gladiator games held at the request of the new emperor Commodus. He has no idea that Maximus is a gladiator in this marathon, he believes he is dead. Maximus and the rest of the troupe get placed in a game that is sure death for them all, but Maximus takes on the leader position and they survive. The whole crowd is amazed, including the new Emperor Commodus. He insists on meeting the brave Spaniard.