Grain supply to the city of Rome

In ancient Rome, the Romans used the term Cura Annonae ("care for the grain supply"), in honour of their goddess Annona and the grain dole was distributed from the Temple of Ceres. The Aedile took care of the grain supply (Cura Annonae) as part of his duties.

In classical antiquity, the grain supply to the city of Rome could not be met entirely from the surrounding countryside, which was taken up by the villas and parks of the aristocracy and which produced mainly fruit, vegetables and other perishable goods. The city therefore became increasingly reliant on grain supplies from other parts of Italy, notably Campania, and from elsewhere in the empire, particularly the provinces of Sicily, North Africa and Egypt. These regions were capable of shipping adequate grain for the population of the capital amounting to 60 million modii (540 million litres / 540,000 cubic metres or 135 million gallons / 16.8 million bushels) annually, according to some sources. These provinces and the shipping lanes that connected them with Ostia and other important ports thus gained great strategic importance. Whoever controlled the grain supply had an important measure of control over the city of Rome.

...
Wikipedia