A few possible reasons present themselves:

Caesar lived at the beginning of the most productive period of literary output in Roman history. From around the middle of his life through end of that of his son's, Roman writers wrote more about the current-event/recent-history political affairs of public life at Rome than they did in any other period. Caesar himself was a major contributor to this output, writing a sprawling narrative of his military campaigns both in Gaul and during the Civil Wars (which forms one of the major sources we have for his life and career, and which is widely praised as the most 'accessible' work of Latin literature which survives from the ancient world, being composed in simple, concise Latin to be read at all levels of Roman society, from the poor citizen to the Senatorial elite), as is Cicero, who wrote an absolutely ENORMOUS number of letters on a wide variety of subjects, especially public affairs (which he discussed at length with his many contacts among the Senatorial elite.)

In addition, Caesar established the foundations of the Imperial regime which his adopted son Augustus would build upon. Although Augustus downplayed much of his father's later autocratic activities and the events of the civil war, writers of Augustus' generation and the early Principate couldn't help but to feel pressured to including glowing references to Caesar in their histories and literary works praising Augustus' new regime. Though they may have privately disliked the legacy of Caesar (which had stripped the Senatorial elite of so much power and replaced it with an autocratic monarchy), the elites and upper-middle-class writers of the period knew that to criticize Caesar would have been to criticize Augustus, and the Imperial regime, and that was a dangerous thing to do (to lesser and greater degrees depending on who was in office.)

Caesar was also something of a culture hero for the Roman people, one who was remembered fondly by the masses for his many kindnesses to them, his reformist legislation, his clemency towards defeated enemies and rivals, and his successes as a Roman general in battle. Caesar was Rome's winning-est general, and his campaigns (both across the Roman world and in his contracted campaigns in Gaul, Germania, and Britain) were the stuff of legend. Caesar won more battles, more often, more consistently, than any other general in the ancient or medieval periods. It would not be until advancements in technology made daily skirmishes and engagements a feature of modern warfare that a general would find himself leading troops in battle more often than Caesar had done 2000 years before. Imperial-era writers considered him 'the Roman Alexander.' The Senate, on Augustus' orders, deified him. To this day, there is an 'altar' in Rome (where Caesar's body was supposedly burned upon his death) where the people of the city lay flowers in honor of the 'greatest Roman who ever lived.'

Sulla, by contrast, was DESPISED by the people of Rome, both elite and common. Even during his lifetime, he was an elitist snob, one who tried to bypass the traditional office of aedile on his way to the praetorship (so that he wouldn't have to throw an expensive set of games) only for the people to smack him down and refuse to grant it to him (in spite of his military successes), and force him to concede to throw them even BETTER games than they would normally expect so that they would vote for him the next time. Although Sulla did win many battles, for most of his career he did so under the command of other men, and it was seen as somewhat grasping on his part for him to claim the glory for those successes (when they traditionally went to the man at the top.) Most of his independent successes (in the Social War and the later Civil War against Marius' supporters) were at the cost of 'fellow Romans' (the Italians who fought Rome in the Social War largely became Roman after the war, and did not remember Sulla fondly for his part in it), but where Caesar was merciful with defeated enemies to the point where it eventually wound up costing him his life, Sulla was merciless and vengeful. Unlike Caesar, who was lucky enough to be able to occupy Rome without needing to seize it from an occupying force, Sulla entered the city at the head of an army on TWO separate occasions, and on both occasions, lots of people died, either trying to keep him out or in the subsequent purges. Furthermore, when he seized power, Sulla stripped the rights of the people's tribunes, a hugely unpopular move. When Sulla finally died, a few short years after being made 'dictator for life' (and then resigning that office when he felt his reforms were secure), he was remembered as a despised tyrant.

When Caesar died, he was remembered (by the masses) as a beloved hero.

Hi there! You’ve asked a question along the lines of ‘why didn’t I learn about X’. We’re happy to let this question stand, but there are a variety of reasons why you may find it hard to get a good answer to this question on /r/AskHistorians.

Firstly, school curricula and how they are taught vary strongly between different countries and even different states. Additionally, how they are taught is often influenced by teachers having to compromise on how much time they can spend on any given topic. More information on your location and level of education might be helpful to answer this question.

Secondly, we have noticed that these questions are often phrased to be about people's individual experiences but what they are really about is why a certain event is more prominent in popular narratives of history than others.

Instead of asking "Why haven't I learned about event ...", consider asking "What importance do scholars assign to event ... in the context of such and such history?" The latter question is often closer to what people actually want to know and is more likely to get a good answer from an expert. If you intend to ask the 'What importance do scholars assign to event X' question instead, let us know and we'll remove this question.

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