The Coat of Arms was introduced by King Richard I of England in the 1190s, apparently as a version of the arms of the Duchy of Normandy. Normandy currently uses two leopards, although an alternative historical version uses three leopards identical to the English arms.
According to one tradition, following the Norman Conquest an extra leopard was added to two existing Norman leopards to represent the combined Anglo-Norman realm. According to another tradition the two leopards were combined with the single leopard of Aquitaine on the acquisition of these continental territories by the English Crown. Other heraldic authorities have claimed that at an early stage in the development of heraldry the number of Norman leopards was not fixed and that it is simply a matter of design as to why England has ended up with three heraldic leopards (now called lions) and Normandy with two.