Skandagupta succeeds Kumaragupta I as ruler of the Gupta Empire in 455.

He may have been the son of a junior wife; it may even be that he was simply a successful general who promoted himself into the ruling Gupta clan.

He certainly had immediately to face some of the greatest challenges in the annals of the empire having to contend with the Pushyamitras and the Hunas (a name by which the "White Huns" are known in India).

He defeats the Pushyamitras, a tribe who had settled in central India but then rebelled.

He is also faced with invading Indo-Hephthalites or Hunas, from the northwest.

Skandagupta had warred against the Hunas during the reign of his father, and is celebrated throughout the empire as a great warrior.

He crushes the Huna invasion in 455, and manages to keep them at bay; however, the expense of the wars drains the empire's resources and contributes to its decline.

...Corsica, ...

The Vandals, with their rule firmly established in what are now northern Tunisia and northeastern Algeria, and their large fleets controlling much of the western Mediterranean, have by this time annexed Sardinia, …

…the Balearic Islands, and …

…parts of Sicily.

Genseric, who is perhaps the most perceptive barbarian king of the fifth century in realizing the total weakness of the empire, rejects the policy of formal alliance with it from 455.

The ninth-century Anglo-Saxon Chronicle mentions the battle of Aylesford in the entry for 455.

According to the text, the Anglo-Saxon leaders Hengist and Horsa fought Vortigern, King of the Britons, in the battle.

Horsa was slain, and Hengist and his son Oisc became the Kings of Kent.

The Historia Brittonum, also written in the ninth century, contains a variant account of the battle.

Chapters 43–45 indicate that Vortigern's son Vortimer, not Vortigern himself, rose against the Saxons and engaged them in four battles.

The third of these battles was fought "at the Ford, in their language called Epsford, though in ours Set thirgabail”.

At this battle Horsa falls, as does Vortimer's brother Catigern.

The Historia does not say who won the battle, saying specifically that during Vortimer's campaign the Saxons "sometimes extended their boundaries by victory, and sometimes were conquered and driven back."

According to the text, the Britons successfully ousted the Saxons at the fourth battle, fought "near the stone on the shore of the Gallic sea".

However, Vortimer's death shortly after ensures the victory is short lived.

The Anglo-Saxon Chronicle account is similarly grim for the Britons, saying that they were forced to forsake Kent for good in 457 following Hengist and Oisc's bloody victory at Crayford.

Maximus, according to John of Antioch, was so irritated by Valentinian’s refusal to appoint him as his magister militum that he decided to have Valentinian assassinated as well.

He chooses as accomplices Optilia and Thraustila, two Scythians who had fought under the command of Aetius and who, after the death of their general, had been appointed as Valentinian’s escort.

Maximus easily persuades them that Valentinian was the only one responsible for the death of Aetius, and that the two soldiers must avenge their old commander, while at the same time also promising them a reward for the betrayal of the Emperor.

Valentinian, who is in Rome, goes on March 16, 455, to Campus Martius with some guards, accompanied by Optilia, Thraustila and their men.

As soon as the Emperor dismounts to practice with the bow, Optilia comes up with his men and hits him in the temple.

As Valentinian turns to look at his attackers, Optilia kills him.

Thraustila at the same moment kills Heraclius.

Most of the soldiers standing close by had been faithful followers of Aetius and none lift a hand to save the emperor.

The two Scythians take the imperial diadem and robe and bring them to Maximus.

The sudden and violent death of Valentinian III leaves the Western Roman Empire without an obvious successor to the throne, with several candidates supported by various groups of the imperial bureaucracy and the military.

In particular, the army’s support is split between three main candidates: Maximianus, the former domesticus ("bodyguard") of Aëtius, who is the son of an Egyptian merchant named Domninus who had become rich in Italy; the future emperor Majorian, who commands the army after the death of Aetius and who has the backing of the Empress Licinia Eudoxia; and Maximus himself, who has the support of the Roman Senate and who in the end, on March 17, defeats his rivals and secures the throne by distributing money to officials of the imperial palace.

After gaining control of the palace, Maximus consolidates his hold on power by immediately marrying Licinia Eudoxia, the widow of Valentinian III.

She only marries him reluctantly, suspecting that in fact he had been involved in the murder of her late husband; and indeed Maximus treats Valentinian III's assassins with considerable favor.

The eastern court at Constantinople has refused to recognize Maximus’s accession, so to further secure his position, Maximus quickly recalls Avitus, appoints him as Master of Soldiers, and sends him on a mission to Toulouse to the court of Theodoric II, who had succeeded to his father, at Toulouse.

This embassy probably confirmed to the new king and his people the condition of foederati of the Empire and asked for their support for the new Emperor.

Maximus also proceeds to cancel the betrothal of Licinia’s daughter, Eudocia, to Huneric, the son of the Vandal king Genseric.

This infuriates the Vandal king, who only needs the excuse of Licinia’s despairing appeal to the Vandal court for help to begin preparations for the invasion of Italy.