Roman emperor

Tiberius Julius Caesar Augustus (/taɪˈbɪəriəs/ ty-BEER-ee-əs; 16 November 42 BC – 16 March AD 37) was Roman emperor from AD 14 until 37. He succeeded his stepfather Augustus, the first Roman emperor. Tiberius was born in Rome in 42 BC to Roman politician Tiberius Claudius Nero and his wife, Livia Drusilla. In 38 BC, Tiberius's mother divorced his father and married Augustus. Following the untimely deaths of Augustus's two grandsons and adopted heirs, Gaius and Lucius Caesar, Tiberius was designated Augustus's successor. Prior to this, Tiberius had proved himself an able diplomat and one of the most successful Roman generals. His conquests of Pannonia, Dalmatia, Raetia, and (temporarily) parts of Germania laid the foundations for the empire's northern frontier.

Early in his career, Tiberius was happily married to Vipsania, daughter of Augustus's friend, distinguished general and intended heir, Marcus Vipsanius Agrippa. They had a son, Drusus Julius Caesar. After Agrippa died, Augustus insisted that Tiberius divorce Vipsania and marry Agrippa's widow, Augustus' own daughter (Tiberius's step-sister) Julia. Tiberius reluctantly gave in. This second marriage proved scandalous, deeply unhappy, and childless; ultimately, Julia was sent into exile by her father. Tiberius adopted his nephew, the able and popular Germanicus, as heir. On Augustus's death in 14, Tiberius became princeps at the age of 55. He seems to have taken on the responsibilities of head of state with great reluctance and perhaps a genuine sense of inadequacy in the role, compared to the capable, self-confident and charismatic Augustus.

Mesopotamia was the name of a Roman province, initially a short-lived creation of the Roman emperor Trajan in 116–117 and then re-established by Emperor Septimius Severus in c. 198. Control of the province was subsequently fought over between the Roman and the Sassanian empires until the Muslim conquests of the 7th century.

Annia Galeria Faustina the Elder, sometimes referred to as Faustina I or Faustina Major (c. 100 – late October 140), was a Roman empress and wife of the Roman emperor Antoninus Pius. The emperor Marcus Aurelius was her nephew and later became her adopted son, along with Emperor Lucius Verus. She died early in the principate of Antoninus Pius, but continued to be prominently commemorated as a diva, posthumously playing a prominent symbolic role during his reign.

The praetorian prefect (Latin: praefectus praetorio; Greek: ἔπαρχος/ὕπαρχος τῶν πραιτωρίων) was a high office in the Roman Empire established by Emperor Augustus in 2 BC. Originating as the commander of the Praetorian Guard, the office gradually acquired extensive legal and administrative functions, with its holders becoming the Emperor's chief aides. Under Constantine I, the office was much reduced in power and transformed into a purely civilian administrative post, while under his successors, territorially defined praetorian prefectures emerged as the highest-level administrative division of the Empire. The prefects again functioned as the chief ministers of the state, with many laws addressed to them by name. In this role, praetorian prefects continued to be appointed by the Eastern Roman Empire (and the Ostrogothic Kingdom) until the reign of Heraclius in the 7th century AD, when wide-ranging reforms reduced their power and converted them to mere overseers of provincial administration. The last traces of the prefecture disappeared in the Byzantine Empire by the 840s.

The term praefectus praetorio was often abbreviated in inscriptions as "PR PR" or "PPO".

The Battle of Verona was fought between the Roman general and usurper Decius, and emperor Philip the Arab in 249. Decius was victorious and Philip and his son Philip II were both killed. Decius was subsequently declared Roman emperor.

Gaius Messius Quintus Trajanus Decius (c. 201 – June 251), known as Trajan Decius or simply Decius (/ˈdiːʃiəs/), was Roman emperor from 249 to 251.

A distinguished politician during the reign of Philip the Arab, Decius was proclaimed emperor by his troops after putting down a rebellion in Moesia. In 249, he defeated and killed Philip near Verona and was recognized as emperor by the Senate afterwards. During his reign, he attempted to strengthen the Roman state and its religion, leading to the Decian persecution, where a number of prominent Christians (including Pope Fabian) were put to death. In the last year of his reign, Decius co-ruled with his son Herennius Etruscus, until they were both killed by the Goths in the Battle of Abritus.

The following is a list of usurpers in the Roman Empire —individuals who unsuccessfully claimed and/or attempted to usurp the throne of a ruling emperor (augustus). The ancient term was "tyrant" (Latin: tyrannus), which had negative connotation in and of itself. Usurpation was common during the whole imperial era; virtually all imperial dynasties rose to power through usurpation and conspiracies. The "imperial office" established by Augustus never defined an stable system of succession, and emperors often had to rely solely on military power to survive.

In the Eastern Roman Empire (395–1453), rebellion and usurpation were so notoriously frequent (in the vision of the medieval West, where usurpation was rare) that the modern term "byzantine" became a byword for political intrigue and conspiracy. For usurpation in the Eastern Roman Empire, see List of Byzantine usurpers.

Justinian I (Latin: Iustinianus, Ancient Greek: Ἰουστινιανός, romanized: Ioustinianós; 482 – 14 November 565), also known as Justinian the Great, was Roman emperor from 527 to 565.

His reign was marked by the ambitious but only partly realized renovatio imperii, or "restoration of the Empire". This ambition was expressed by the partial recovery of the territories of the defunct Western Roman Empire. His general, Belisarius, swiftly conquered the Vandal Kingdom in North Africa. Subsequently, Belisarius, Narses, and other generals conquered the Ostrogothic Kingdom, restoring Dalmatia, Sicily, Italy, and Rome to the empire after more than half a century of rule by the Ostrogoths. The praetorian prefect Liberius reclaimed the south of the Iberian Peninsula, establishing the province of Spania. These campaigns re-established Roman control over the western Mediterranean, increasing the Empire's annual revenue by over a million solidi. During his reign, Justinian also subdued the Tzani, a people on the east coast of the Black Sea that had never been under Roman rule before. He engaged the Sasanian Empire in the east during Kavad I's reign, and later again during Khosrow I's reign; this second conflict was partially initiated due to his ambitions in the west.

Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian (Latin: Octavianus), was the founder of the Roman Empire, who reigned as the first Roman emperor from 27 BC until his death in AD 14. The reign of Augustus initiated an imperial cult and an era of imperial peace (the Pax Romana or Pax Augusta) in which the Roman world was largely free of armed conflict. The Principate system of government was established during his reign and lasted until the Crisis of the Third Century.

Octavian was born into an equestrian branch of the plebeian gens Octavia. Following the assassination of Julius Caesar in 44 BC, Octavian was named in Caesar's will as his adopted son and heir, and inherited Caesar's name, estate, and the loyalty of his legions. He, Mark Antony, and Marcus Lepidus formed the Second Triumvirate to defeat the assassins of Caesar. Following their victory at the Battle of Philippi (42 BC), the Triumvirate divided the Roman Republic among themselves and ruled as de facto oligarchs. The Triumvirate was eventually torn apart by the competing ambitions of its members; Lepidus was exiled in 36 BC, and Antony was defeated by Octavian's naval commander Marcus Agrippa at the Battle of Actium in 31 BC. Antony and his wife Cleopatra, the Ptolemaic queen of Egypt, killed themselves during Octavian's invasion of Egypt, which then became a Roman province.

The 1st century BC, also known as the last century BC and the last century BCE, started on the first day of 100 BC and ended on the last day of 1 BC. The AD/BC notation does not use a year zero; however, astronomical year numbering does use a zero, as well as a minus sign, so "2 BC" is equal to "year –1". 1st century AD (Anno Domini) follows.

In the course of the century, all the remaining independent lands surrounding the Mediterranean Sea were steadily brought under Roman control, being ruled either directly under governors or through puppet kings appointed by Rome. The Roman state itself was plunged into civil war several times, finally resulting in the marginalization of its 500-year-old Roman Republic, and the embodiment of total state power in a single man—the Roman emperor.