Question: Who was the mother of the leader under which the empire that had Aelia Eudocia as a citizen, reached its greatest extent?

<P0-S0> The imperial period of Rome lasted approximately 1,500 years compared to the 500 years of the Republican era. <P0-S1> The first two centuries of the empire's existence were a period of unprecedented political stability and prosperity known as the Pax Romana, or ``Roman Peace ''. <P0-S2> Following Octavian's victory, the size of the empire was dramatically increased. <P0-S3> After the assassination of Caligula in AD 41, the Senate briefly considered restoring the republic, but the Praetorian Guard proclaimed Claudius emperor instead. <P0-S4> Under Claudius, the empire invaded Britannia, its first major expansion since Augustus. <P0-S5> After Claudius' successor, Nero, committed suicide in AD 68, the empire suffered a series of brief civil wars, as well as a concurrent major rebellion in Judea, during which four different legionary generals were proclaimed emperor. <P0-S6> Vespasian emerged triumphant in AD 69, establishing the Flavian dynasty, before being succeeded by his son Titus, who opened the Colosseum shortly after the eruption of Mount Vesuvius. <P0-S7> His short reign was followed by the long reign of his brother Domitian, who was eventually assassinated. <P0-S8> The Senate then appointed the first of the Five Good Emperors. <P0-S9> The empire reached its greatest extent under Trajan, the second in this line. <SEP> <P1-S0> under the terms of the concluding treaty of versailles signed in 1919, the empire reached its greatest extent with the addition of 1,800,000 square miles (4,700,000 km2) and 13 million new subjects. <P1-S1> the colonies of germany and the ottoman empire were distributed to the allied powers as league of nations mandates. <P1-S2> britain gained control of palestine, transjordan, iraq, parts of cameroon and togo, and tanganyika. <P1-S3> the dominions themselves also acquired mandates of their own: the union of south africa gained south-west africa (modern-day namibia), australia gained german new guinea, and new zealand western samoa. <P1-S4> nauru was made a combined mandate of britain and the two pacific dominions. <SEP> <P2-S0> in 1729, nader shah, a chieftain and military genius from khorasan, successfully drove out and conquered the pashtun invaders. <P2-S1> he subsequently took back the annexed caucasian territories which were divided among the ottoman and russian authorities by the ongoing chaos in iran. <P2-S2> during the reign of nader shah, iran reached its greatest extent since the sassanid empire, reestablishing the iranian hegemony all over the caucasus, as well as other major parts of the west and central asia, and briefly possessing what was arguably the most powerful empire at the time. <SEP> <P3-S0> Aelia Eudocia Augusta (; Late Greek: Αἰλία Εὐδοκία Αὐγούστα; 401 – 460 AD), also called Saint Eudocia, was a Greek Eastern Roman Empress by marriage to Byzantine emperor Theodosius II (r. 408–450), and a prominent historical figure in understanding the rise of Christianity. <P3-S1> Eudocia lived in a world where Greek paganism and Christianity existed side-by-side with both pagans and non-orthodox Christians being persecuted. <P3-S2> Although Eudocia's work has been mostly ignored by modern scholars, her poetry and literary work are great examples of how her Christian faith and Greek heritage were intertwined, exemplifying a legacy that the Roman Empire bequeathed on the Christian world. <SEP> <P4-S0> Marcus Ulpius Traianus was born on 18 September 53AD in the Roman province of Hispania Baetica (in what is now Andalusia in modern Spain), in the city of Italica (now in the municipal area of Santiponce, in the outskirts of Seville). <P4-S1> Although frequently designated the first provincial emperor, and dismissed by later writers such as Cassius Dio (himself of provincial origin) as "an Iberian, and neither an Italian nor even an Italiot", Trajan appears to have hailed on his father's side from the area of Tuder (modern Todi) in Umbria, at the border with Etruria, and on his mother's side from the Gens Marcia, of an Italic family of Sabine origin. <P4-S2> Trajan's birthplace of Italica was founded as a Roman military colony of "Italian" settlers in 206BC, though it is unknown when the Ulpii arrived there. <P4-S3> It is possible, but cannot be substantiated, that Trajan's ancestors married local women and lost their citizenship at some point, but they certainly recovered their status when the city became a municipium with Latin citizenship in the mid-1st century BC.