Armor became a very important piece of weaponry very early in the advent of man.  When flying objects such as rocks, stones or the claws of wild animals intruded on man, he quickly realized he had to protect himself.  The first armor was animal skin, and later this was combined with  bone to add additional protection.  The evolution continued as sophisticated leather armor was developed,  and spikes were added for additional protection.  Rome developed the Lorica Segmentata armor which in itself is a symbol of the Empire.  Breastplate armor was used as early as the Sumerians, and is still popular today with soldiers around the world.  Wearable plate armor was popular from Medieval to the Renaissance eras.