Battle of Cannae
Capua had defected to Hannibal after the Battle of Cannae in 216 BC. Hannibal had made Capua his winter quarter in 215 BC and had conducted his campaigns against Nola and Casilinum from there. The Romans had recaptured Casilinum, crucial for attacking Capua, in 214 BC. Since then they had conducted annual raids during harvest time to prevent the Capuans from gathering provisions.