Heraldry is is not only seen in medieval times but in Egyptian they saw clay tablets that had symbols and designs they put them up on the walls to say that they defeated them. In medieval times the person to use heraldry was heraldic for the English it was not just a way of telling who you wear it was what rank. they would also put they coat of arms on stain glass windows.Coat of arms started when people started mailing letters and they would stamp it with wax coat of arms.Then they put them on shields so crest became a requirement of knights