What were the reasons why the Romans managed to establish an empire that covered most of Europe, North Africa and the Middle East?

The Romans were not content with conquering land near to them. They realised that land further away might also have riches in them that would make Rome even more wealthy. Hence their drive to conquer Western Europe.

Explanation:

gaius cassius longinus and marcus junius brutus, former enemies of julius caesar who'd joined the roman senate, led caesar's assassination, dubbing themselves "the liberators." and the second one is   the assassination of julius caesar was the result of a conspiracy by many roman senators led by gaius cassius longinus, decimus junius brutus albinus, and marcus junius brutus. they stabbed caesar (23 times) to death in a location adjacent to the theatre of pompey on the ides of march 15 march 44 bc.