Julius Caesar was one of the most important people of Ancient Rome. He expanded Rome's territory, granted citizenship to those who didn't live in Italian provinces, and created a public works program to create more jobs.
Augustus (also known as Octavian) was become the leader of Rome after his great-uncle Julius Caesar was assasinated. He started the Pax Romana (peaceful time period of Ancient Rome), doubled the size of the empire, and expanded roads.
Pompey was important because he defeated the Mithridates and got the people from the Middle East all te way to the Euphrates River under Roman control. He formed the First Triumvirate with Julius Caesar and Crassus.
The Romans created concrete, which was used to build things like buildings and aqueducts.
Since Rome was so big, they created one of the best systems of roads to exist. They were very straight and curved to drain water.
The Romans were the first people to successfully use arches in architecture. They realized how well they supported structures, so they used them on buildings and in bridges.