Johannes was a high-ranking civil servant under Honorius. When the emperor died there was no clear successor and Johannes was proclaimed Augustus with the help and approval of a former Honorius general. Johannes's title was immediately contested by Theodosius II who stood to gain politically by aligning himself with Constantius III's widow, Galla Placidia, and her infant son Valentinian III. Accordingly, an army was sent to crush Johannes and he was captured, publicly ridiculed, mutilated and then executed.
RIC 1901, Depeyrot 12/1 Solidus Obv: DNIOHANNESPFAVG - Diademed (rosettes), draped and cuirassed bust right. Rev: VICTORIAAVGGG Exe: R/V/COMOB - Johannes standing right, stepping on captive, holding labarum and Victory on globe. 423-425 (Ravenna). $3,000 1/13/03.
RIC 1903, Depeyrot 12/2 Semissis Obv: DNIOHANNESPFAVG - Diademed (rosettes), draped and cuirassed bust right. Rev: VICTORIAAVGVSTORVM Exe: COMOB - Victory seated right, holding shield with Chi-Ro inside, genius below and to right also holding shield. $2,344 4/1/01.