They preferred to get the portrait of renowned people, the statues that fully resembled the actual person like the statue of Cicero.
There was a common perception that keeping good pictures of the acquaintances would help their ghosts after death to remain happy. This perception helped the art form to flourish during the Roman Republic and Roman Empire (Kidipede, 2009).
The Greek art influenced the Roman sculpture. For example in Augustus’ Ara Pacis (the Altar of Peace) reflects the Greek art in the swirls at the front, in the frieze and in the meanders below the frieze. In history, it so happened that the Romans started winning battles with Greece around 200 BC. Roman soldiers while parading in Greece saw their art forms in their temples, cemeteries, public squares and in the houses of Greeks. While returning back to Rome, they took Greek sculptors along to work for them (Kidipede, 2009).
Roman art got enriched with new ideas by the third century. Element of war appeared prominently because of war with Germany and the bloodshed. The effect can be seen in the column of Marcus Aurelius where people are shown beheaded and without guts; they are depicted as suffering. Artists made more use of drill than chisel for easy sculpturing which provided a distinct feel of the sculptor
Concerns of the soul got manifested in the art forms which were due to presence of Christians in the Roman Empire. Eyes of the persona are shown as looking towards heaven or gods, symbolizing spirituality. Rest of the body parts like arms, legs and head are not shown in proportion, showing least concern to the significance of the body.
As there were no battles in the fourth century AD, warfare portraiture decreased but spiritual element remained prominent through big eyes and unbalanced bodies till the dethroning of the Roman Empire.
Roman sculpture was unique form in itself by focusing on the individuality aspect in it although