 (Julian would state in late November that he set off down this road "because, having been declared a public enemy, I meant to frighten him [Constantius] merely, and that our quarrel should result in intercourse on more friendly terms...")

However, in June, forces loyal to Constantius captured the city of Aquileia on the north Adriatic coast, an event that threatened to cut Julian off from the rest of his forces, while Constantius's troops marched towards him from the east.Aquileia was subsequently besieged by 23,000 men loyal to Julian.All Julian could do was sit it out in Naissus, the city of Constantine's birth, waiting for news and writing letters to various cities in Greece justifying his actions (of which only the letter to the Athenians has survived in its entirety).