greek member family relative byzantine emperor senior military figure reign governor secured imperial possessions western balkans serbs appointed fleets turkish suppressed rebellions crete cyprus recovered western coast byzantium biography early life born circa second son ton son john wife maria bulgaria granddaughter bulgaria john brother law married sister rebellion norman mercenary john elder brother michael grandfather estates demanded hostages return releasing wounded father held captive elder agreed imprisoned michael managed escape younger john remained defeat capture turks later year father died john remained grandfather estates raised learned rebellion informed departed joined forces officially proclaimed emperor governor recovered strategically important adriatic port city occupied installed military governor local province john remained replaced son emperor brother tenure apparently successful john repelled serbian incursions according captured king restoring power client byzantine_empire john managed restore order region albania suffered greatly byzantine norman wars previous years surviving correspondence archbishop testimony success john departure post expressed nostalgia time governorship asked advice appointment campaigns turks recalled constantinople john appointed post commander chief byzantine navy known usually credited hold post evidence existence late holder named john tasked naval threat posed turkish byzantine vassal built fleet seized islands raided proclaimed emperor participating condemned leo john set forth island troops marched coast point opposite island crossed fleet recovered meet combined byzantine force laid siege months offered island exchange safe passage john agreed turks set sail ships arrived attacked managed escape fleet captured sunk victory reinforced defences led fleet recover islands conquered returning constantinople return constantinople tasked late early suppression revolts crete cyprus rebellion subdued easily news imperial fleet approach caused counter coup cyprus initial resistance overcome captured soon installed island new governor fleet returned constantinople surrender byzantines named john commander chief byzantine army tasked recovering turks avoid conflict facilitate negotiations given custody wife sultan daughter captured john gave command fleet marched short siege agreed surrender city exchange safe departure guarantees inhabitants safety readily accepted took possession city naming governor assume duties murdered muslim enraged sailors fleet people city unable restored order massacre run course left experienced general city entire fleet secure city continued campaign john marched south defeated turkish garrison long battle took captives islands installed john army turned inland took cities philadelphia entrusted reached opened gates marched fortresses installing governor reached turks survived fled having caught surprise army defeated took booty later life longer mentioned campaign known monastic documents point retired monastery assumed monastic date death known dated mentioned alive explicitly mentioned having died
John Doukas (megas doux)