oc as ▁( r . ▁ 6 0 2 – 6 1 0 ). ▁He ▁is ▁also ▁known ▁to ▁have ▁had ▁an ▁il leg it imate ▁son , ▁John , ▁who ▁was ▁sent ▁as ▁a ▁host age ▁to ▁the ▁Av ars ▁in ▁ 6 2 2 . ▁▁ ▁At ▁this ▁time , ▁the ▁By z antine ▁Empire ▁was ▁engaged ▁in ▁a ▁prolong ed ▁struggle ▁with ▁its ▁large ▁eastern ▁ant agon ist , ▁the ▁S ass an id ▁Pers ian ▁Empire . ▁Over ▁the ▁previous ▁twenty ▁years , ▁Pers ian ▁arm ies ▁had ▁scored ▁victory ▁after ▁victory ▁and ▁captured ▁most ▁of ▁the ▁By z antine ▁Lev ant . ▁In ▁ 6 2 2 , ▁after ▁se cur ing ▁peace ▁with ▁the ▁Av ars ▁in ▁the ▁B alk ans , ▁Her ac lius ▁set ▁out ▁to ▁campaign ▁in ▁person ▁against ▁the ▁Pers ians . ▁Bon us ▁was ▁left ▁behind ▁in ▁Constantin ople ▁as ▁the ▁Emperor ' s ▁deput y ▁and ▁guard ian ▁of ▁his ▁young ▁sons , ▁together ▁with ▁Patri arch ▁Ser g ius . ▁During ▁Her ac lius ' s ▁absence ▁on ▁campaign ▁for ▁the ▁next ▁years , ▁Bon us ▁acted ▁as ▁the ▁effective ▁reg ent ▁of ▁the ▁By z antine ▁Empire . ▁ ▁The ▁exact ▁offices ▁Bon us ▁held ▁are ▁unclear ; ▁he ▁held ▁the ▁rank ▁of ▁patri ki os , ▁and ▁in ▁the ▁sources ▁he ▁is ▁usually ▁simply ▁referred ▁to ▁as ▁" the ▁mag ist ros ". ▁Although ▁this ▁would ▁usually ▁imply ▁the ▁position ▁of ▁mag ister ▁offic ior um , ▁The