During the Second Punic War with Carthage, Rome's earliest known annalists Quintus Fabius Pictor and Lucius Cincius Alimentus recorded history in Greek, and relied on Greek historians such as Timaeus. Roman histories were not written in Classical Latin until the 2nd century BCE with the Origines by Cato the Elder. Contemporary Greek historians such as Polybius wrote about the rise of Rome during its conquest of Greece and ascension as the primary power of the Mediterranean in the 2nd century BCE. Moving away from the annalist tradition, Roman historians of the 1st century BCE such as Sallust, Livy, and even Julius Caesar wrote their works in a much fuller narrative form. While Caesar's De Bello Gallico focused specifically on his wars in Gaul, Roman works that served as a broad universal history often placed heavy emphasis on the origin myth of the founding of Rome as a starting point. These works formed the basis of the Roman historiographic models utilized by later Imperial authors of the Principate era, such as Tacitus and Suetonius.

Before the Second Punic War, there was no historiography in Rome, but the clash of civilisations it involved proved a potent stimulus to historiography, which was taken up by the two senators (and participants in the war), Quintus Fabius Pictor and Lucius Cincius Alimentus, who may be considered the "Founders" of Roman Historiography. Pictor wrote a history of Rome in Greek, not Latin. This choice of writing about the war in Greek arose from a need to address the Greeks and counter another author, Timaeus, who also wrote a history of Rome until the Second Punic War. Timaeus wrote with a negative view of Rome. Therefore, in defense of the Roman state, Pictor wrote in Greek, using Olympiad dating and a Hellenistic style. Pictor's style of writing history defending the Roman state and its actions, and using propaganda heavily, eventually became a defining characteristic of Roman historiography, while he is also known for the establishment of the ab urbe condita tradition of historiography which is writing history "from the founding of the city".

Cincius also wrote in Greek, but seems to have been less esteemed by later historians: thus for the Battle of Lake Trasimene, Livy states that he "has accepted Fabius as my main source, since he was contemporary with this war", whereas earlier, on the question of Hannibal's numbers, he says that "the most authoritative account should be that of Lucius Cincius Alimentus...but Cincius makes a mess of the numbers".

After Pictor wrote, many other authors followed his lead, inspired by the new literary form: Gaius Acilius, Aulus Postumius Albinus, and Cato the Elder. Cato the Elder is credited as the first historian to write in Latin. His work, the Origines, was written to teach Romans what it means to be Roman. Like Pictor, Cato the Elder wrote ab urbe condita, and the early history is filled with legends illustrating Roman virtues. The Origines also spoke of how not only Rome, but the other Italian towns were venerable, and that the Romans were indeed superior to the Greeks.

The Romans enjoyed serious endeavors and so the writing of historiography became very popular for upper class citizens who wanted to spend their time on worthwhile, virtuous, "Roman" activities. As idleness was looked down upon by the Romans, writing history became an acceptable way to spend their otium or retirement.

Almost as soon as historiography started being used by the Romans, it split into two traditions: the annalistic tradition and the monographic tradition.

The authors who used the Annalistic tradition wrote histories year-by-year, from the beginning, which was most frequently from the founding of the city, usually up until the time that they were living in.

Some annalistic authors: