Commentarii de Bello Gallico
Commentarii de Bello Gallico (Commentaries on the Gallic War) is a historical book by Julius Caesar, describing in third person the warfare and intrigues he undertook over 9 years spent subjugating Gaul. The book was one of two (the other being The History of the Decline and Fall of the Roman Empire by Edward Gibbon) that heavily influenced Edward Sallow and the principles of strategy and organization of Caesar's Legion.
There are two sources Caesar (IIRC) refers to: Gibbons’ The History of the Decline and Fall of the Roman Empire and Julius Caesar’s Commentarii de Bello Gallico (Commentaries on the Gallic War).
It is certainly possible that he read other primary sources. Based on Arcade’s education, it’s likely that the Followers of the Apocalypse had access to other Roman and Greek literature, including writings by Sallust and Lucan.
As Arcade and Caesar both know Latin, it is likely that the textbooks they used also contained snippets of Roman literature and quotes as sententiae antiquae (very common in Wheelock’s and many other books). Because the primary purpose of contemporary (i.e., 20th/21st century) Latin education is typically not conversation or writing, but comprehension of classic literature, the use of these quotes/references is common, though often without context.
E.g., a student may learn that “festina lente” means “hasten slowly,” but may not know that it came from Suetonious who was quoting Augustus who, in turn, had borrowed the adage from Greek in the first place. And even if they did learn all that, the Followers might not have access to Suetonious’ text, De vita Caesarium.”— J.E. Sawyer on the novels in the Fallout universe
- Fallout: New Vegas Official Game Guide Collector's Edition p.459: "Rebirth of the Son of Mars
The adolescence and young adulthood of the man who calls himself Caesar were spent as a scribe of the Followers of the Apocalypse. While this boy had a quick mind, he made for a scribe of uneven ability, for his success in academics was equal to his interest in the subject assigned. Nor was he a favorite among his fellows. Though athletic, handsome, and petulance held him back. He never felt that he belonged among the Followers, and blamed them for it. their rigorous devotion to scholarship was stifling, their mission to ensure that humanity would never repeat the mistakes of the Great War was ridiculously naive. The boy longed for something more.
When the time came for the boy to leave the Boneyard and trek the wastes as part of a nine-person expedition, wanderlust soon curdled into disappointment. The primitive conditions of the tribes the expedition encountered disgusted him. Inferior people all, wretched in their squalor. Still, he seemed to discern, amid the chaos of their petty struggles and everyday atrocities, the true order of the wastes-and it was one of anonymous, amoral liberty. The wastes called to the boy as a blank slate upon which a man of will could write his own destiny.
During the same period of the time that the boy was coming to these insights, the expedition uncovered a cache of well-preserved historical texts. Among with adventure fiction and comic books, history had always been his favorite subject, and so the task of cataloguing and studying the texts fell to him. Though the boy had long been aware of basic facts concerning many ancient empires, these new texts filled in many previously obscure details. Reading The History of the Decline and Fall of the Roman Empire rendered him a veritable hermit for two weeks. But even that could not have prepared him for the Commentarii, the account of the military campaigns of Gaius Julius Caesar, written by the man himself. Reading Commentarii changed the boy's life. Unfortunately, it was destined to change the lives of thousands more, and for the worse.
In Gaius Julius Caesar the boy found a man who seamed to have fulfilled the full measure of potential greatness allotted to him by fate, a man whose career spanned political accomplishment and military achievement in equal measure. Such adventure! And intrigue! And cool uniforms! The boy's frustrations with his lot in life gained sharp focus. In reading about Caesar, he was like an ant scurrying about the feet of a regal statue. He resolved that he would go to any lengths necessary to change the course of his life. The Commentarii would be his blueprint. In an illiterate, benighted world, who would ever know that Caesar was not his original creation?
That night, Caesar offered a different sort of assistance to a tribe his expedition had contacted recently: weapons, medical supplies, and tactical expertise. He led several tribal accomplices back to the expedition's camp and through its defenses, and there oversaw the murder of his eight fellows. Within a week he was leading the tribe on ever more ambitious raids against neighboring bands of raiders and tribals."
(Behind the Bright Lights & Big City)