what places made up the western roman empire?
Europe North Africa Middle East
entailment
 Historians see the growing Roman influence over the east , as with the west , as not a matter of intentional empire @-@ building , but constant crisis management narrowly focused on short @-@ term goals within a highly unstable , unpredictable , and inter @-@ dependent network of alliances and dependencies . With some major exceptions of outright military rule , the Roman Republic remained an alliance of independent city @-@ states and kingdoms ( with varying degrees of independence , both de jure and de facto ) until it transitioned into the Roman Empire . It was not until the time of the Roman Empire that the entire Roman world was organized into provinces under explicit Roman control . 

entailment
 The Roman Empire was among the most powerful economic , cultural , political and military forces in the world of its time . It was the largest empire of the ancient history era , and one of the largest empires in world history . At its height under Trajan , it covered 5 million square kilometers , a territory composed of 48 nations in the 21st century . It held sway over an estimated 70 million people , at that time 21 % of the world 's entire population . The longevity and vast extent of the empire ensured the lasting influence of Latin and Greek language , culture , religion , inventions , architecture , philosophy , law and forms of government on the empire 's descendants . Throughout the European medieval period , attempts were even made to establish successors to the Roman Empire , including the Empire of Romania , a Crusader state , and the Holy Roman Empire . By means of European colonialism following the Renaissance , and their descendant states , Greco @-@ Roman culture was exported on a worldwide scale , playing a crucial role in the development of the modern world . 

entailment
 The Roman Empire ( Latin : Imperium Rōmānum ; Classical Latin : [ ɪmˈpɛ.ri.ũː roːˈmaː.nũː ] Koine and Medieval Greek : Βασιλεία τῶν Ῥωμαίων , tr . Basileia tōn Rhōmaiōn ) was the post @-@ Roman Republic period of the ancient Roman civilization , characterized by government headed by emperors and large territorial holdings around the Mediterranean Sea in Europe , Africa and Asia . The city of Rome was the largest city in the world c . 100 BC – c . 400 AD , with Constantinople ( New Rome ) becoming the largest around 500 AD , and the Empire 's populace grew to an estimated 50 to 90 million inhabitants ( roughly 20 % of the world 's population at the time ) . The 500 @-@ year @-@ old republic which preceded it was severely destabilized in a series of civil wars and political conflict , during which Julius Caesar was appointed as perpetual dictator and then assassinated in 44 BC . Civil wars and executions continued , culminating in the victory of Octavian , Caesar 's adopted son , over Mark Antony and Cleopatra at the Battle of Actium in 31 BC and the annexation of Egypt . Octavian 's power was then unassailable and in 27 BC the Roman Senate formally granted him overarching power and the new title Augustus , effectively marking the end of the Roman Republic . 

neutral
 " The spread of urban trading networks , and their extension along the Persian Gulf and eastern Mediterranean , created a complex molecular structure of regional foci so that as well as the zonation of core and periphery ( originally created around Mesopotamia ) there was a series of interacting civilizations : Mesopotamia , Egypt , the Indus Valley ; then also Syria , central Anatolia ( Hittites ) and the Aegean ( Minoans and Mycenaeans ) . Beyond this was a margin which included not only temperate areas such as Europe , but the dry steppe corridor of central Asia . This was truly a world system , even though it occupied only a restricted portion of the western Old World . Whilst each civilization emphasized its ideological autonomy , all were identifiably part of a common world of interacting components . " 

entailment
 The Empire reached its largest expanse under Trajan ( reigned 98 – 117 ) , encompassing an area of 5 million square kilometers that as of 2009 was divided among forty different modern countries . The traditional population estimate of 55 – 60 million inhabitants accounted for between one @-@ sixth and one @-@ fourth of the world 's total population and made it the largest population of any unified political entity in the West until the mid @-@ 19th century . Recent demographic studies have argued for a population peak ranging from 70 million to more than 100 million . Each of the three largest cities in the Empire — Rome , Alexandria , and Antioch — was almost twice the size of any European city at the beginning of the 17th century . 
