Guidon (heraldic flag)

In heraldry and vexillology, a heraldic flag is any of several types of flags, containing coats of arms, heraldic badges, or other devices used for personal identification.

When it is for the personal use of a monarch, it is a royal standard.

Heraldic flags include banners, standards, pennons and their variants, gonfalons, guidons, and pinsels. Specifications governing heraldic flags vary from country to country, and have varied over time.

The pennon is a small elongated flag, either pointed or swallow-tailed (when swallow-tailed it may be described as a banderole). It was charged with the heraldic badge or some other armorial ensign of the owner, and displayed on his own lance, as a personal ensign. The pennoncelle was a modification of the pennon.

In contemporary Scots usage, the pennon is four feet long. It tapers either to a point or to a rounded end as the owner chooses. It is assigned by the Lord Lyon King of Arms to any armiger who wishes to apply for it.

The banner of arms (also simply called banner) is square or oblong and larger than the pennon, bearing the entire coat of arms of the owner, composed precisely as upon a shield but in a square or rectangular shape.

In the olden time, when a Knight had distinguished himself by conspicuous gallantry, it was the custom to mark his meritorious conduct by prompt advancement on the very field of battle. In such a case, the point or points of the good Knight’s Pennon were rent off, and thus the ... small Flag was reduced to the square form of the Banner, by which thenceforth he was to be distinguished

The banners of members of Orders of Chivalry are typically displayed in the Order's chapel. Banners of Knights of the Order of the Thistle are hung in the 1911 chapel of the Order in St Giles High Kirk in Edinburgh. Banners of Knights of the Order of the Garter are displayed in St George's Chapel at Windsor Castle. From Victorian times Garter banners have been approximately 5 feet by 5 feet.

...
Wikipedia