Slovakia in the Roman era
The reign of Augustus (27 BC - 14 AD) began a long period known as the Pax Romana, or Roman peace. Despite continuous wars on the frontiers, and one year-long civil war over the imperial succession, the Mediterranean world remained at peace for more than two centuries. Augustus enlarged the empire dramatically, annexing Egypt, Dalmatia, Pannonia, and Raetia, expanded possessions in Africa, and completed the conquest of Hispania.
By the end of his reign, the armies of Augustus had conquered the Alpine regions of Raetia and Noricum (modern Switzerland, Bavaria, Austria, Slovenia), Illyricum and Pannonia (modern Albania, Croatia, Hungary, Serbia, etc.).
Reign of Marcus Aurelius
Although Marcus Aurelius shows no personal affection for Hadrian (significantly, he does not thank him in the first book of his "Meditations"), he presumably believed it his duty to enact the man's succession plans. Thus, although the senate planned to confirm Marcus Aurelius alone, he refused to take office unless Lucius received equal powers. The senate accepted, granting Lucius the "imperium", the tribunician power, and the name Augustus. Marcus Aurelius became, in official titulature, Imperator Caesar Marcus Aurelius Antoninus Augustus; Lucius, forgoing his name Commodus and taking Marcus Aurelius' family name, Verus, became Imperator Caesar Lucius Aurelius Verus Augustus. It was the first time that Rome was ruled by two emperors.