Leo III the Isaurian
The original Greek term ("despotēs") meant simply "lord" and was synonymous with ("kyrios"). As the Greek equivalent to the Latin "dominus", "despotēs" was initially used as a form of address indicating respect. As such it was applied to any person of rank, but in a more specific sense to God, bishops and the patriarchs, and primarily the Roman and Byzantine Emperors, occasionally used in formal settings, for example on coins (since Leo III the Isaurian) or formal documents.