Being a good strategist is not necessarily about winning battles, but making the right/favourable preparations and choosing the right conditions for a battle. There are three realms where warfare are concerned: strategy, tactics, and logistics. All are important, but the latter is almost always neglected by amateurs such as Adolf Hitler.
Caius Julius Caesar is particularly well-known for his campaigns in Galia Transalpina (France). He was fortunate enough to keep the gaulic tribes at odds with each other during most of his stay, but responded competently when they united under Vercingetorix. Caesar also fought the loyalists for control of the Roman Empire, and defeated Pompeius Magnus at Pharsalus.
Caesar had the benefit of mostly fighting disorganised and easily startled Gauls during most of his career, not to mention incompetent enemy commanders. Yet his genius was probably more in being able to combine good generalship with very shrewd politicking. He was extremely indebted during most of his career and hounded by Senators that wanted his head because they saw him as a demagogue. Caesar's only choices were to surrender and be forced into some ignominious and inglorious life or to press onward to become the new king of Rome.
He crossed the the River Rubicon with only 5,000 men and forced the Senate to flee the eternal city. He left Mark Antony in his stead to manage affairs in Rome while he campaigned (he had a sound judgment of people) in Greece. It should be noted that Caesar was uncommonly lucky (until the end) and ever so daring. Even though he did not always start the battle with the enemy, he usually forced his enemies to fight him on his own terms. He was very active as a commander and very good at promoting loyalty among the ranks (both thanks to praise and loot). He always took contingency precautions such as when he called for the aid of Mithradates of Pergamum when Caesar was besieged by the Egyptians in Alexandria.
However, take note that there were other very good Roman generals such as Pompeius Magnus, Mark Antony, Caius Marius, Lucius Sulla and Scipio Africanus. All of these are known to history and some even fought more distinguished battles than Caesar, but unfortunately they are neither as significant nor as popular as Caesar.
**sorry it was so long, sum it up if ya need to/**
