The Latin term speculum regum appears as early as the 12th century and may have been used even earlier.
These texts most frequently take the form of textbooks for the instruction of kings, princes, or lesser rulers on successful governance and behaviour.
The term is also used for histories or literary works presenting model images of good and bad kings.
Authors often composed such "mirrors" at the accession of a new king, when a young and inexperienced ruler was about to come to power.
Notable examples of Carolingian textbooks for kings, counts and other laymen include: Irish texts