The arms of the Regensburg Schottenklöster, which date from at least the 14th century, combined the arms of the Holy Roman Emperor (from whom the abbey received protection) dimidiated with a symbol that may be linked with the crest of the O'Brien dynasty arms (an 11th-century O'Brien is listed as the "fundator" of the abbey).
Due to the early practice of marshalling by dividing the marshalled arms through the middle of the charge (called "dimidiation"), some charges took on the appearance of being themselves divided, such as the arms of Hochtaunuskreis.