Khan Academy: Bronze Head From a Statue of the Emperor Hadrian

Hadrian (reigned 117-138 C.E.), once a tribune in three different legions of the Roman army and commander of a legion in one of Trajan's wars, was often shown in military uniform. He was clearly keen to project the image of an ever-ready soldier, but other conclusions have been drawn from his surviving statues. When Hadrian inherited the Roman Empire, his predecessor, Trajan's military campaigns had over-stretched it. He ruthlessly put down rebellions and strengthened his borders. He built defensive barriers in Germany and Northern Africa.