Mirrors for princes or mirrors of princes (Latin: specula principum) was a literary genre of didactic political writings throughout the Middle Ages and the Renaissance. It was part of the broader speculum or mirror literature genre. The Latin term speculum regum appears as early as the 12th century and may have been used even earlier. It may have developed from the popular speculum literature popular from the 12th to 16th centuries, focusing on knowledge of a particular subject matter. 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. One could view them as a species of prototypical self-help book or study of leadership before the concept of a "leader" became more generalised than the concept of a monarchical head-of-state.One of the earliest works was written by Sedulius Scottus (fl. 840–860), the Irish poet associated with the Pangur Bán gloss poem (c. 9th century). Possibly the best known European "mirror" is The Prince (c. 1513) by Niccolo Machiavelli, although this was not the most typical example. Source: Wikipedia (en)