▁the ▁main ▁parts ▁from ▁the ▁time ▁of ▁Const antine , ▁running ▁around ▁the ▁monument , ▁one ▁strip ▁above ▁each ▁later al ▁arch way ▁and ▁including ▁the ▁west ▁and ▁east ▁sides ▁of ▁the ▁arch . ▁These ▁" histor ical " ▁relief s ▁dep ict ▁scenes ▁from ▁the ▁Italian ▁campaign ▁of ▁Const antine ▁against ▁Max ent ius ▁which ▁was ▁the ▁reason ▁for ▁the ▁construction ▁of ▁the ▁monument . ▁The ▁fr ie ze ▁starts ▁at ▁the ▁western ▁side ▁with ▁the ▁Depart ure ▁from ▁Milan ▁( Pro fect io ). ▁It ▁continues ▁on ▁the ▁southern , ▁face , ▁with ▁the ▁Sie ge ▁of ▁Ver ona ▁( O bs id io ) ▁on ▁the ▁left ▁( S outh ▁west ), ▁an ▁event ▁which ▁was ▁of ▁great ▁importance ▁to ▁the ▁war ▁in ▁Northern ▁Italy . ▁On ▁the ▁right ▁( S outh ▁east ) ▁is ▁dep icted ▁the ▁Battle ▁of ▁Mil v ian ▁Bridge ▁( Pro el ium ) ▁with ▁Const antine ' s ▁army ▁vict orious ▁and ▁the ▁enemy ▁d row ning ▁in ▁the ▁river ▁T iber . ▁On ▁the ▁eastern ▁side , ▁Const antine ▁and ▁his ▁army ▁enter ▁Rome ▁( In gress us ); ▁the ▁artist ▁seems ▁to ▁have ▁avoided ▁using ▁imag ery ▁of ▁the ▁triumph , ▁as ▁Const antine ▁probably ▁did ▁not ▁want ▁to ▁be ▁shown ▁triumph ant ▁over ▁the ▁E ternal ▁City . ▁On ▁the ▁northern ▁face , ▁looking ▁towards ▁the ▁city , ▁are ▁two ▁stri ps ▁with ▁the ▁em peror ' s ▁actions ▁after ▁taking ▁possession ▁of ▁Rome . ▁On ▁the ▁left ▁( N orth