337 Succeeds his father as ruler in the east; his brothers Constantinus II and Constans receive the west and Italy
338 Meets the other rulers in Viminacium; Constans victorious against the Sarmatians; accepts the titles Sarmaticus Maximus; the Sasanian king Shapur II invades Mesopotamia and occupies Armenia; Constantius to Syria; accepts the title Persicus
339 Consul II (with Constans)
340 Constantinus II attacks Constans, but is defeated and killed
342 Consul III (with Constans II)
343 Battle of Singara; Constantius accepts the title Adiabenicus Maximus
346 Consul IV (with Constans III)
348 Constantius defeats the Persians in the Second battle of Singara
350 Revolt of Magnentius; Constans killed; revolt of Vetranio; revolt of Nepotianus; Shapur II besieges Nisibis; death of Nepotianus; Vetranio resigns
351 Constantius Gallus made caesar; marries to Constantina (daughter of Constantine I the Great)
Constantius II
351 Battle of Mursa; Magnentius defeated
353 Consul VI (with Gallus II); suicide of Magnentius; Constantius is sole ruler of the Roman empire
354 Consul VII (with Gallus III); war against the Alamans; execution of Gallus Caesar; pagan temples closed
355 Military operations in Raetia; revolt of Silvanus in Cologne; he is immediately killed; Julianus proclaimed caesar
356 Consul VIII (with Julian); pagan cults forbidden; Julian liberates Cologne; war against the Alamans; death of Vetranio
357 Consul IX (with Julian II); Constantius' state visit to Rome; Julian defeats the Alamans near Argentoratum and campaigns beyond the Rhine
358 Fruitless negotiations with Shapur II; Constantius successfully campaigns against the Sarmatians, Quadi, and Limigantes; Barbatio repels an attack of the Juthungi on Raetia; Julian attacks the Franks along the Meuse
359 Julian again across the Rhine; fall of Barbatio; Constantius' second campaign against the Limigantes; the Persians capture Amida; treason trials
360 Consul X (with Julian III); Shapur II invades Mesopotamia, takes Singara and Bezabde; Constantius to the east, fails to recapture Bezabde; Julian proclaimed emperor, attacks the Franks
361 Constantius in Mesopotamia, prepares war against Julian; dies during his march to the west