Knights in the middle ages had their own thing that identified them called a coat of arms. Here is a couple examples of what a coat of arms looked like.
A coat of arms was a sign like an animal or a flag or something printed on a shield. That picture on the shield would identify the knight who wore it. The knight who owned this shield might have slain a dragon and that may be why his sign is a dragon. Here is another example of a coat of arms.
This coat of arms might have belonged to a man with a powerful sword that shined like fire. A knight could have any kind of picture on his coat of arms. The middle ages that took place in Europe was just about the same as in England
In the middle ages the only people who could read and write were monks-people who did nothing but study, work, and pray. In the middle ages the monks wrote artistically meaning they put pictures around the page they wrote on. At the beginning of every sentence instead of a plain capital letter they put a large letter with a picture. Back in the middle ages the picture on the writing could be of anything. It could be of a picture of a church or a knight or anything. Monks in the middle ages liked to put illustration or pictures on their writing.