A symbol is a visual image that represents something other than itself. It may be a representation using an object, picture, written word, sound or a particular mark.
During the 18th and the 19th centuries, several symbols were used by artists and revolutionaries to depict abstract concepts. These symbols were usually popular images from everyday life that uneducated masses could easily identify with.
During revolutions, artists represented a nation as a person. This personification gave life to an abstract concept like nation.
The way of expressing an abstract idea like freedom or liberty through a symbol that may be person or thing is known as allegory. An allegory has a literal and a symbolic meaning. In the nineteenth century, French artists used the female allegory to represent France. She was named Marianne, She symbolises reason, liberty and the ideals of the republic.
In Germany, the allegory for the nation was again a female figure called Germania. A Broken chain represented abolition of slavery.
A fasces or a bundle of rods with an axe in the middle was used to symbolize strength in unity. The red Phrygian cap signified freedom of a slave. It was also known as the liberty cap. French people wore these caps a few days before the storming of the Bastille.