Heraldry, for those who like that sort of thing, is a fabulous study. It is one side of a pentagonal subject matter, along with: vexillology, ceremony, rank and pedigree. Arthur Fox-Davies, in A Complete Guide to Heraldry, described heraldry as 'the shorthand of history'. In that sentiment, I think he is on to something. This is because heraldry goes well beyond notions of blue blood, monarchy, or bygone ages, as it also speaks to modern individuals, organisations, towns, cities, and regions.
The precursors of modern heraldry date back thousands of years. An example of which can be seen in the top row of the Narmer Palette (circa 3100 BC) which depicts four men bearing standards — above which is a serekh denoting pharaoh's name: Narmer. Similar use of heraldic symbols is featured in art from ancient Mesopotamia; including some of the first recorded images of griffins — magical beasts that would prove a recurrent theme in later ages.
Though truly ancient in origin, heraldry, as we understand it today, dates more properly from anno Domini than before Christ. Maddeningly, for an author who is quite keen about #OnThisDay events, there is no clear date on which the ancient transitions to the modern when it comes to heraldic forms. Taking some key objects from the Middle-Ages, for example the Bayeux Tapestry, which illustrates the Norman invasion of England that occurred in 1066, there are depictions of shields, sails, and pennants, some of which are emblazoned with typical heraldic symbols — such as crosses and dragons. Yet tantalisingly, none of this imagery recurs with the same individual, leading to the conclusion they are more decorative than sigils of peoples' houses.