Here you can see a list of historical events that are not that accurate in some movies.
Gladiator: Marcus Aurelius Didn’t Die During the Battle
In the 2000 Russell Crowe movie, Marcus Aurelius was murdered by his own son, Commodus, during a battle in the Marcomannic War. The real Marcus Aurelius died in what is now Vienna, in 180 AD. Aurelius gave succession to Commodus in real life, which is a lot different than being murdered by him.