Nerva died in 98 AD and his successor and heir was the general Trajan.
Trajan was born in a non-patrician family from Hispania Baetica (modern-day Andalusia) and his preeminence emerged in the army, under Domitian.
He is the second of the Five Good Emperors, the first being Nerva.
Trajan was greeted by the people of Rome with enthusiasm, which he justified by governing well and without the bloodiness that had marked Domitian's reign.
He freed many people who had been unjustly imprisoned by Domitian and returned private property that Domitian had confiscated; a process begun by Nerva before his death.

Trajan conquered Dacia (roughly modern-day Romania and Moldova), and defeated the king Decebalus, who had defeated Domitian's forces.
In the First Dacian War (101–102), the defeated Dacia became a client kingdom; in the Second Dacian War (105–106), Trajan completely devastated the enemy's resistance and annexed Dacia to the Empire.
Trajan also annexed the client state of Nabatea to form the province of Arabia Petraea, which included the lands of southern Syria and northwestern Arabia.
He erected many buildings that survive to this day, such as Trajan's Forum, Trajan's Market and Trajan's Column.
His main architect was Apollodorus of Damascus; Apollodorus made the project of the Forum and of the Column, and also reformed the Pantheon.
Trajan's triumphal arches in Ancona and Beneventum are other constructions projected by him.
In the Second Dacian War, Apollodorus made a great bridge over the Danube for Trajan.

Trajan's final war was against Parthia.
When Parthia appointed a king for Armenia who was unacceptable to Rome (Parthia and Rome shared dominance over Armenia), he declared war.
He probably wanted to be the first Roman leader to conquer Parthia, and repeat the glory of Alexander the Great, conqueror of Asia, whom Trajan next followed in the clash of Greek-Romans and the Persian cultures.
In 113 he marched to Armenia and deposed the local king.
In 115 Trajan turned south into the core of Parthian hegemony, took the Northern Mesopotamian cities of Nisibis and Batnae, organized a province of Mesopotamia (116), and issued coins announcing that Armenia and Mesopotamia was under the authority of the Roman people.
In that same year, he captured Seleucia and the Parthian capital Ctesiphon (near modern Baghdad).
After defeating a Parthian revolt and a Jewish revolt, he withdrew due to health issues.
In 117, his illness grew and he died of edema.
He nominated Hadrian as his heir.
Under Trajan's leadership the Roman Empire reached the peak of its territorial expansion; Rome's dominion now spanned 5.0 million square kilometres (1.9 million square miles).
Nerva died in 98 AD and his successor and heir was the general Trajan. Trajan was born in a non-patrician family from Hispania Baetica (modern-day Andalusia) and his preeminence emerged in the army, under Domitian. He is the second of the Five Good Emperors, the first being Nerva. Trajan was greeted by the people of Rome with enthusiasm, which he justified by governing well and without the bloodiness that had marked Domitian's reign. He freed many people who had been unjustly imprisoned by Domitian and returned private property that Domitian had confiscated; a process begun by Nerva before his death.
Trajan conquered Dacia (roughly modern-day Romania and Moldova), and defeated the king Decebalus, who had defeated Domitian's forces. In the First Dacian War (101–102), the defeated Dacia became a client kingdom; in the Second Dacian War (105–106), Trajan completely devastated the enemy's resistance and annexed Dacia to the Empire. Trajan also annexed the client state of Nabatea to form the province of Arabia Petraea, which included the lands of southern Syria and northwestern Arabia. He erected many buildings that survive to this day, such as Trajan's Forum, Trajan's Market and Trajan's Column. His main architect was Apollodorus of Damascus; Apollodorus made the project of the Forum and of the Column, and also reformed the Pantheon. Trajan's triumphal arches in Ancona and Beneventum are other constructions projected by him. In the Second Dacian War, Apollodorus made a great bridge over the Danube for Trajan.
Trajan's final war was against Parthia. When Parthia appointed a king for Armenia who was unacceptable to Rome (Parthia and Rome shared dominance over Armenia), he declared war. He probably wanted to be the first Roman leader to conquer Parthia, and repeat the glory of Alexander the Great, conqueror of Asia, whom Trajan next followed in the clash of Greek-Romans and the Persian cultures. In 113 he marched to Armenia and deposed the local king. In 115 Trajan turned south into the core of Parthian hegemony, took the Northern Mesopotamian cities of Nisibis and Batnae, organized a province of Mesopotamia (116), and issued coins announcing that Armenia and Mesopotamia was under the authority of the Roman people. In that same year, he captured Seleucia and the Parthian capital Ctesiphon (near modern Baghdad). After defeating a Parthian revolt and a Jewish revolt, he withdrew due to health issues. In 117, his illness grew and he died of edema. He nominated Hadrian as his heir. Under Trajan's leadership the Roman Empire reached the peak of its territorial expansion; Rome's dominion now spanned 5.0 million square kilometres (1.9 million square miles).
Ancient Rome