Between 1135 and 1155 A.D., Coats of Arms began appearing in Europe. They were displayed on the shields of knights and passed down from gerneration to gernation in a family. The oldest known coat of arms mentioned was where King Henry I of England supposedly gave his son-in-law, Geoffrey Plantagenet, in 1127 A.D a coat that consisted of an azure shield that bore four gold lions. One theory as to why they were created was so knights could remain recognizable to their allies when covered in armor. The more likely reason was just for mere self aggrandizement. The art of blazoning, assigning, and marshalling a coat of arms is called heraldry.(1)

Most of the symbols that appear on a "Coat of Arms" have a specific meaning, but some are believed to only have artistic value. Some of the most symbolic images are those that depict animals. For example, a bear is representative of strength, cunning, and the protection of one's kin. The boar is thought to be symbolic of bravery because in the wild boars tend to fight to the death. Doves were a common symbol on a "Coat of Arms" and they had the same meaning then as they do to this day, love and peace. (2)

COLORS	Even the colors can have special meaning in a "family crest" or coat of arms:
Gold (Or)	Generosity and elevation of the mind
Silver or White (Argent)	Peace and sincerity
Red (Gules)	Warrior or martyr; Military strength and magnanimity
Blue (Azure)	Truth and loyalty
Green (Vert)	Hope, joy, and loyalty in love
Black (Sable)	Constancy or grief
Purple (Purpure)	Royal majesty, sovereignty, and justice
Orange (Tawny or Tenne)	Worthy ambition
Maroon (Sanguine or Murray)	Patient in battle, and yet victorious

(1)
(3)

"The Coats of Arms that the Knights carried into battle. They represented who they fought for under their King and Country."
This is an example of Sir Galahad's Coat of Arms. The Colors are of his respective country.

(1)http://www.fleurdelis.com/coatofarms.htm
(2)http://www.fleurdelis.com/meanings.htm
(3)http://www.camelotdesign.co.uk/images/shield2.gif