Several notables of the Roman Republic were named Marcus Atilius Regulus. By far the most notable was:

Marcus Atilius Regulus (died c. 250 BC) was a general and consul (for the second time) in the ninth year of the First Punic War (256 BC). Regulus conquered the Sallentini and captured Brundisium (now Brindisi) during his first term as consul in 267 BC.

He was one of the commanders in the Punic naval expedition which shattered the Carthaginian fleet at Cape Ecnomus, and landed an army on Carthaginian territory. The invaders were so successful that the other consul, L. Manlius Vulso, was recalled to Rome, Regulus being left behind to finish the war.

After a severe defeat at Adys near Carthage, the Carthaginians were inclined for peace, but the terms proposed by Regulus were so harsh that they resolved to continue the war. The Cathaginians replaced the outmatched general Hamilcar Barca with new leadership and in 255 BC, Regulus was completely defeated at Bagradas. He was taken prisoner by the Spartan mercenary general Xanthippus along with 500 of his men.

There is no further trustworthy information about him. According to tradition, he remained in captivity until 250 BC, when after the defeat of the Carthaginians at Panormus he was sent to Rome on parole to negotiate a peace or exchange of prisoners. On his arrival he strongly urged the Roman Senate to refuse both proposals, and honored his parole by returning to Carthage where he was tortured to death (Horace, Odes, iii. 5). This story made Regulus to the later Romans the type of heroic endurance; but most historians regard it as insufficiently attested, Polybius being silent. The tale might have been invented by the annalists to excuse the cruel treatment of the Carthaginian prisoners by the Romans.