Heraldy goes back to ancient times. It is the way in which an aristocrat identified himself. Each man had a shield on which was a design. With so many men having such coats of arms, someone had to keep a record, and provide new designs when they were needed. The people who do this are called "Heralds". In England, the College of Arms is the authority who does this:College of Arms In Scotland, these are the people: The Court of the Lord Lyon - Homepage
There were similar organizations throughout Europe.