The Vigla, also known as the Arithmos and in English as the Watch, was one of the elite tagmata of the Byzantine army. It was established in the latter half of the 8th century, and survived until the late 11th century. Along with the Noumeroi regiment, the Vigla formed the guard of the imperial palace in Constantinople, and was responsible for the Byzantine emperor's safety on expeditions.

John Kourkouas, also transliterated as Kurkuas or Curcuas, was one of the most important generals of the Byzantine Empire. His success in battles against the Muslim states in the East reversed the course of the centuries-long Arab–Byzantine wars and set the stage for Byzantium's eastern conquests later in the century.