Born to a Roman aristocratic family from Pannonia Savia, Orestes was son of Tatulus, a pagan, and son-in-law to Romulus, who served as comes in the Western Roman Empire. After Pannonia was ceded to Attila the Hun, Orestes joined Attila's court, reaching high position as a secretary (notarius) in 449 and 452. In 449, Orestes was sent by Attila twice to Constantinople as envoy to Emperor Theodosius II.
In 475, Orestes was appointed magister militum and patricius by Western Roman Emperor Julius Nepos. This proved to be a mistake on the part of Nepos. By August 28, 475, Orestes, at the head of the foederati levies, managed to take control of the government in Ravenna, which had been the de facto capital of the Western Roman Empire since 402. Julius Nepos fled without a fight to Dalmatia, where he would continue to reign until his assassination in 480. With the emperor far away, Orestes elevated his son Romulus to the rank of Augustus, so that the last Western Roman emperor is known as Romulus Augustulus meaning "little Augustus" as the emperor was only a 15-year-old boy at the time he became emperor in 475.
The new administration was not recognized by the rival Eastern Roman Emperors Zeno and Basiliscus, who still considered Julius Nepos to be their legitimate partner in the administration of the Empire. But as they were engaged in a civil war with each other, neither emperor was about to oppose the latest usurper in battle.
Orestes was free to issue new solidi in the mints of Arles, Milan, Ravenna and Rome, enabling him to pay the barbarian mercenaries who constituted most of the Roman Army at the time. [citation nedeed]
However, Orestes denied the demands of Heruli, Scirian and Torcilingi mercenaries to be granted Italian lands in which to settle. Before he overthrew Nepos, the Roman general promised his barbarian soldiers a third of Italian territory in exchange for assisting with the deposition of the emperor. After being turned down by Orestes, the dissatisfied mercenaries revolted under the germanic Odoacer, whom they declared to be their king on August 23, 476. Odoacer led them against their former employer, ravaging every town and village in northern Italy and meeting little resistance. Orestes fled to the city of Pavia, where the city's bishop gave him sanctuary within the city walls. Despite the protection he received from the bishop, Orestes was forced to flee for his life when Odoacer and his men broke through the city defenses and ravaged the church, stealing all the money that the bishop had collected for the poor and razing many of the city buildings to the ground.
After escaping from the city of Pavia, Orestes rallied the few surviving units of Roman troops stationed in northern Italy and was able to move his small army to the city of Piacenza. The forces of Odoacer and Orestes finally met on the battlefield, but the inexperienced Roman commander and his few and sparse Imperial troops, disorganized and unprepared, stood no chance against the savagery of Odoacer's mercenary army. The majority of the Roman soldiers were either killed, captured, or driven off, while Orestes was captured near the city on August 28 and was swiftly executed. Within weeks, Ravenna was captured and Romulus Augustus was deposed. Eighteenth-century historian Edward Gibbon attached great significance to this event due to Odoacer's foreign birth. Gibbon's romantic description of the events of 476 as the fall of the Western Roman Empire was influential for two centuries, but modern scholarship has tended to question this - it was the end of the emperors in the West. On the other hand the Roman Empire existed wherever the emperor could appoint his officials to govern them. Nevertheless, Odoacer's defeat of Orestes and his son are often still used to mark the transition from Late Antiquity to the Early Middle Ages which is itself disputable as many scholars[according to whom?] see a continuity of culture and society.