In 212 BC, during the Second Punic War, the Romans were suffering crushing defeats against Hannibal and the Carthaginians, despite one good victory at Syracuse. Frustrated, they consulted with Marcius, an ancient seer, for his reading of the Sibylline Oracles and the Carmina Marciana. He advised them to hold games in honor of the Greek god of the sun, Apollo, for his aid in banishing the Carthaginians from Italy. The games were called the Ludi Apollinares. This is a category of roman republic coins.
The oracle laid out the management of the games. The praetor urbanis was responsible for supervising the games. Ten men were assigned the sacrifices according to Greek rites. The senate, under advisement of the oracle, set the payment to the praetor as 12,000 ases to be used for the sacrifices and other expenditures. The sacrifices to Apollo were very specific too – a bull with gilt horns and two white goats with gilt horns. Along with the other sacrifices, an offering was also made of a heifer with gilt horns to Latona, Romanized Greek goddess of Leto, mother of Apollo.
The games in 212 BC were held in the Circus Maximus and only lasted one day. Citizens all gave a contribution to help defray the expenses. Spectators wore chaplets for the celebration. Matrons performed supplications, everyone ate their meals in the propatulum (an unroofed area) with open doors, and the entire day was filled with ceremonies and various rites. C. Sulla was praetor at that time.
In 211 BC, the praetor Calpurnius made a proposal and the senate decreed the games should be held again, along with the renewal of the vows. Originally, the games were an appeal to Apollo for the specific purpose of his assistance in the war, but four years later, in 208 BC, a plague broke out in Rome and the surrounding area. The senate decided to bring the games back and make them a permanent event. When they were held varied during 211-209 BC, but in 208 BC when the plague hit, the praetor urbanis, P. Licinius Varus, brought a bill forward to declare the Ludi Apollinares to be held on Pridie Nonas Quintilis (the day before the Nones of Quintilis, or July 6).
Livy has an alternate history of the games. He suggested that C. Calpurnius Piso made the games permanent in 211 BC, instead of P. Licinius Varus in 208 BC. The two versions seem to overlap with the senatorial decrees, but Livy maintains since the annual games continued without disruption from 212 BC onward, the focus of the games was to appeal to Apollo for victory, instead of protection of the public health against plague.
Regardless of the reasons of health or victory, the games continued over the next two centuries, becoming an eight-day festival beginning on July 6 and the primary sacrifice occurring at the end of the celebration, on July 13.