Signum manus
Medieval European practice of signing with a type of monogram or royal cypher / From Wikipedia, the free encyclopedia
Signum manus (transl. sign of the hand, sometimes also known as Chrismon) refers to the medieval European practice of signing a document or charter with a special type of monogram or royal cypher. The practice is documented from at least the Merovingian period (ca. 5th century) until the 14th century in the Frankish Empire and its successors.