Final answer:
The subject of the student's question is the Roman Emperor Trajan, celebrated for expanding the Roman Empire and enhancing its infrastructure and welfare. His successors included Hadrian, who built fortifications like Hadrian's Wall, and the Julio-Claudian emperors, including Augustus, who is revered for establishing Rome's period of prosperity and order.
Step-by-step explanation:
The individual described in the student's question is most likely the Roman Emperor Trajan. He is known for significantly expanding the Roman Empire during his reign from 98 to 117 CE, including the conquest of Dacia and military victories against the Parthian Empire. Trajan is also celebrated for his efforts to improve Rome's infrastructure, initiating welfare programs such as loans for farmers and funding for the alimentary institution which fed poor children. His focus on the well-being of both the empire and its capital's citizens were hallmark features of his administration.
After Trajan, Emperor Hadrian succeeded him, known for consolidating the empire's borders rather than pursuing expansionist policies. Hadrian's most notable project was the construction of Hadrian's Wall in Britain, a monumental fortification designed to defend the empire against northern tribes and consolidate Roman territory. Meanwhile, the Julio-Claudian emperors, starting with Augustus, worked on expanding the empire, initiating construction projects, and establishing the dominion of Roman culture across its provinces. Augustus, often considered the first Roman Emperor, established a period of peace and prosperity known as the Pax Romana, built a police force, the Praetorian Guard, and was deified posthumously.