then who was?
Antoninus Pius
Marcus Aurelius
In 156, Antoninus turned 70. He found it difficult to keep himself upright without stays. He started nibbling on dry bread to give him the strength to stay awake through his morning receptions. As Antoninus aged, Marcus would take on more administrative duties, more still when he became the praetorian prefect (an office that was as much secretarial as military) when Marcus Gavius Maximus died in 156 or 157. In 160, Marcus and Lucius were designated joint consuls for the following year. 
when did the roman empire end and start It officially started in 27 BC, got split into the Western and Eastern Roman Empires in between and ended with the fall of Constantinople in 1453. who was the ruler then? UNANSWERABLE what was the status of women then? Freeborn Roman women were considered citizens throughout the Republic and Empire, but did not vote, hold political office, or serve in the military. what was the government structure like? The three major elements of the Imperial Roman state were the central government, the military, and provincial government. can you name any personality from this entire empire be it a man or a woman? Emperors Augustus, Caligula, Hadrian, Marcus Aurelius among many other illustrious rulers. from which family did the fourth person originate? Through his grandmother Rupilia, Marcus was a member of the Nerva-Antonine dynasty. which are the good emperors of this dynasty? The so-called "Five Good Emperors" were Nerva, Trajan, Hadrian, Antoninus Pius and Marcus Aurelius. has this last emperor succeeded the third one? No, he was not the immediate successor to Hadrian.
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Marcus Aurelius [SEP] Antoninus Pius' last years
As Antoninus aged, Marcus would take on more administrative duties, more still when he became the praetorian prefect (an office that was as much secretarial as military) when Marcus Gavius Maximus died in 156 or 157. In 160, Marcus and Lucius were designated joint consuls for the following year. Antoninus may have already been ill. Two days before his death, the biographer reports, Antoninus was at his ancestral estate at Lorium, in Etruria, about 19 kilometres (12 mi) from Rome. He ate Alpine cheese at dinner quite greedily. In the night he vomited; he had a fever the next day.