Flavius Julius Constans, also called Constans I, was Roman emperor from 337 to 350. He held the imperial rank of caesar from 333, and was the youngest son of Constantine the Great.

Aquileia is an ancient Roman city in Italy, at the head of the Adriatic at the edge of the lagoons, about 10 kilometres (6 mi) from the sea, on the river Natiso, the course of which has changed somewhat since Roman times. Today, the city is small, but it was large and prominent in classical antiquity as one of the world's largest cities with a population of 100,000 in the 2nd century AD and is one of the main archaeological sites of northern Italy. In late antiquity the city was the first city in the Italian Peninsula to be sacked by Attila the Hun.