the 14th century. In Italy, the Ghibelline faction (the faction loyal to the Emperor in the drawn-out conflict between emperors and popes) began to display or an eagle sable in chief of their coats of arms, known as capo dell'impero or "chief of the empire". Similarly, German cities began to incorporate the Imperial Eagle into their seals and coats of arms to imply Imperial immediacy. From such usage, use of the heraldic eagle by the end of the medieval period became so strongly associated with the Holy Roman Empire that the eagle was rarely used as an independent heraldic charge. Examples of continued use of an eagle in coats of arms based on traditions of the 13th century include the Polish, Moravian, and Silesian coats of arms. By far the oldest and most common manner of depicting the eagle in heraldry is what would come to be known as displayed (éployée), in direct imitation of Roman iconography. The eagle's body is depicted with lateral symmetry, but its head is facing the dexter side. In late medieval blasons, the term "eagle" (Middle French egle) without specification refers to an "eagle displayed". In early modern English terminology, it became common to use "eagle displayed". Also specific to English heraldry is the distinction between "eagle displayed with its wings elevated" and "eagle displayed with wings inverted". This is due to a regional English convention of depicting the tips of the wings pointing upward, while in continental heraldry, the tips of the wings were depicted downward ("inverted"). Later, English heraldry partially adopted the continental convention, leading to a situation where it was unclear whether the two forms should be considered equivalent. In German heraldry, no attitude other than "eagle displayed with wings inverted" ever became current, so that the simple blason of "eagle" (Adler) still refers to this configuration. There is a gradual evolution of the standard depiction of the heraldic eagle over the course of the 12th to 16th centuries. In the 12th to 13th century, the head is raised and the beak is closed. The leading edge of the wings (in German heraldry termed Sachsen or Saxen, representing the main bones in the bird's wing, humerus and ulna) are rolled up at the ends into a spiral shape, with the remiges shown vertical. The tail is represented as a number of stiff feathers. By the later 14th century, the head is straightened,