This is an ancient Roman statue, one of the few original bronzes that have survived.

Marcus Aurelius on horseback,  Capitolio, Rome    ( A Creative Commons Attribution-Share Alike 3.0 Unported license photo by Radomil published here)

How did it manage that?
For centuries the rider was thought to be Constantine, the emperor who made Christianity the official religion of the Roman Empire. So it was not melted down like other pagan works.
By the time it was found out that the rider was the Stoic Marcus Aurelius, the old pagan world was actually venerated and those Renaissance Humanists were delighted to have not only a beautiful relic from their ideal world but the portrait of one of its greatest “philosopher-kings”.

Michelangelo’s design for Capitol Hill

Engraving by Étienne Dupérac (1525-1604), 1568. A public domain photo published here

A replica stands in the middle of the main square of the Capitoline Hill of Rome. The whole square, including the facades of those buildings and the statue’s pedestal, was designed by Michelangelo. The statue makes a strange impression. The rider seems too big for the animal and his feet hang as though he were riding a donkey. Don’t forget that all the riders of the ancient world, including emperors, rode without stirrups, which hadn’t been invented. There is a twist or side-ways movement to the horse, as you sometimes see when real horses pass by in a parade; and it is easy to imagine you are standing there 1800 years ago, watching the emperor come.

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