The Order of the Garter
The royal coat of arms features a blue garter (a strap used to hold up stockings) which the phrase Honi soit qui mal y pense. (Shame on him who thinks ill of it) written on it
You are not alone in wondering why the british royal coat of arms include an item of underclothing and a strange phrase on it?
The answer dates back hundreds of years to the reign of Kind Edward III and the founding of the noble Order of the Garter.
The story goes that in 1348 Joan, Countess of Salisbury was dancing with King Edward when her garter dropped down her leg. Seeing her embarrassment the good king picked it up and bound it about his own leg saying "Honi soit qui mal y pense". At that time the noble people of the English court commonly spoke French rather than English.
Whether this story is true or not, in 1348 Edward founded the order of
the garter. It comprises 24 knights (plus royals).