"Joannes or John (Latin: Iohannes; died June or July 425) was western Roman emperor from 423 to 425.
On the death of the Emperor Honorius (15 August ...
423), Theodosius II, the remaining ruler of the House of Theodosius, hesitated in announcing his uncle's death. In the interregnum, Honorius's patrician at the time of his death, Castinus, elevated Joannes as emperor." - (en.wikipedia.org 11.08.2021)
