Emperor Justin I, a career soldier with little knowledge of statecraft, has wisely surrounded himself with trusted advisors.

The most prominent of these, of course, is his nephew Flavius Petrus Sabbatius, whom he adopts as his son and invests with the name Iustinianus (Justinian).

Justin’s sister Vigilantia (born about 455) had married one Sabbatius and had two children: Petrus Sabbatius Justinian and Vigilantia (born about 490), who had married Dulcissimus and had Praejecta (born about 520), married to the senator Areobindus and Justin II (born about 520).

Vitalian, the general and erstwhile rebel, becomes consul in 520 and is shortly later murdered, probably on the orders of Justinian.

Relying upon the accounts of the historian Procopius, it often has been said that Justinian ruled the Empire in his uncle's name during the reign of Justin; however, there is much evidence to the contrary.

The information from the Secret History of Procopius was published posthumously.

Critics of Procopius (whose work reveals a man seriously disillusioned with his rulers) have dismissed his work as a severely biased source, being vitriolic and pornographic, but without other sources, critics have been unable to discredit some of the assertions in the publication.

However, contrary to the secret history, Justinian was not named as successor until less than a year before Justin's death.

He spends thirty-seven hundred pounds of gold during a celebration in 520.

Justin's reign is noteworthy for the resolution of the Acacian Schism between the eastern and western branches of the Christian church.

As a devout Catholic, Justin endorses Rome's view on the question of the dual nature of Christ and the more general principle of Roman supremacy.

This temporary eastern deferral to the western church will not endure, however.

Justin, the commander of the palace guard, had secured the imperial throne on the death of Emperor Anastasius in July 518.

Unlike his predecessor, Justin supports orthodoxy, and in 518-519 had been instrumental in ending the Acacian schism with Rome and persecutes the dissident Monophysites.

In 523, he also issues an edict against Arianism.

This offends the Arian king Theodoric of the Ostrogoths, who forces Pope John I to visit Constantinople to plead for a mitigation of the edict.

Justin then grants some concessions to the Arians but not enough to satisfy Theodoric.

In the East, the struggle with Persia makes it important for Constantinople to retain control of the small Christian kingdom of Lazica (modern Colchis, a region in Georgia), to secure allies in Mesopotamia and southern Syria, and to counter Persian penetration into Arabia by an understanding with Ethiopia.

On the northern frontier, the Slavs are already crossing the Danube River and troubling the Balkan provinces, and Justin proves unable to repel them.

Intermittent wars have occurred between the Lombards, or Langobards, and the Gepidae, who are allied to Constantinople, from 536.

When Alboin succeeds his father, Audoin, about 563 or 565, the Lombards occupy Noricum and Pannonia (now in Austria and western Hungary), while their long-standing enemies the Gepidae border them on the east in Dacia (now Hungary).

As is customary among the Lombards, Alboin had taken the crown after an election by the tribe's freemen, who traditionally select the king from the dead sovereign's clan.

Shortly afterwards, in 565, a new war erupts with the Gepids, now led by Cunimund.

According to multiple sources, the former king, Thurisind,had been Cunimund's own father, and the enmity that both had for the Lombards was allegedly partly a result of Alboin's murder of Cunimund's brother (Thurisind's son), Turismod.

The true cause of the conflict is uncertain, as the sources are divided; the Lombard Paul the Deacon accuses the Gepids, while the Byzantine historian Menander Protector places the blame on Alboin, an interpretation favored by historian Walter Pohl.

An account of the war by the Byzantine Theophylact Simocatta sentimentalizes the reasons behind the conflict, claiming it originated with Alboin's vain courting and subsequent kidnapping of Cunimund's daughter Rosamund, that Alboin proceeded then to marry.

The tale is treated with skepticism by Walter Goffart, who observes that it conflicts with the Origo Gentis Langobardorum, where she was captured only after the death of her father.

The Gepids obtain the support of the Emperor in exchange for a promise to cede him the region of Sirmium, the seat of the Gepid kings.

Thus, in 565 or 566, Justinian's successor Justin II sends his son-in-law Baduarius as magister militum (field commander) to lead an imperial army against Alboin in support of Cunimund, ending in the Lombards' complete defeat.

Justinian, who had always had a keen interest in theological matters and actively participated in debates on Christian doctrine, has become even more devoted to religion during the later years of his life.

When he dies, on November 14, 565, he leaves the empire exhausted by his wars and public spending, but enriched by his law code and monuments.

Justinian's body is entombed in a specially built mausoleum in the Church of the Holy Apostles (the tomb will be desecrated and robbed during the pillage of Constantinople in 1204 by the Latin States of the Fourth Crusade).

Along with Justin, the kouropalates, another of the late emperors’ nephews, Justin, son of the late Germanus, is the leading contender for the vacant throne, due to his titles and reputation as a commander, as well his army's proximity to the imperial capital.

The former, however, is already present at Constantinople, and can count on the support of the Senate, and especially of Patriarch John Scholasticus and the Count of the Excubitors Tiberius (the future Tiberius II), whom he had helped secure his post.

Callinicus, the praepositus sacri cubiculi, seems to have been the only witness to his dying moments, and later claimed that Justinian had designated "Justin, Vigilantia's son" as his heir in a deathbed decision.

Modern historians suspect Callinicus may have fabricated the last words of Justinian to secure the succession for his political ally, who is the son of Justinian’s sister Vigilantia, and married to Sophia, the niece of the late Empress Theodora.

In any case, Callinicus starts alerting those most interested in the succession, originally various members of the Byzantine Senate.

Then they jointly inform Justin and Vigilantia, offering the throne.

Justin accepts after the traditional token show of reluctance, and with his wife Sophia, he is escorted to the Great Palace of Constantinople.

The Excubitors block the palace entrances during the night, and early in the morning, John Scholasticus, Patriarch of Constantinople, crowns the new Augustus.

Only then is the death of Justinian and the succession of Justin publicly announced in the Hippodrome of Constantinople.

Both the Patriarch and Tiberius, commander of the Excubitors, had been recently appointed, with Justin having played a part in their respective appointments, in his role as Justinian's curopalates.

Their willingness to elevate their patron and ally to the throne is hardly surprising.

In the first few days of his reign Justin pays his uncle's debts, administers justice in person, and proclaims universal religious toleration.

Contrary to his uncle, Justin relies completely on the support of the aristocratic party.

Proud of character, and faced with an empty treasury, he discontinues Justinian's practice of buying off potential enemies.

Immediately after his accession, Justin halts the payment of subsidies to the Avars, ending a truce that has existed since 558.

According to the contemporary historian Evagrius Scholasticus, the two Justins had reached an agreement whereby whoever would be crowned emperor would make the other the "second man" in the empire.

When Justin II recalls his cousin to Constantinople, it seems that this is the reason.

The general is warmly received at first, but soon the new emperor begins to make accusations against him, dismisses his bodyguard and places him under house arrest, before sending him to exile in Alexandria, ostensibly as the new augustal prefect of Egypt.

The general Justin is murdered in his sleep in Alexandria in 565, ostensibly because he was plotting to seize the throne, and his head is cut off and brought to Constantinople.

In reality, he was too great a threat to the new emperor to be left alive; the Visigoth chronicler John of Biclaro explicitly attributes the murder to the wife of Justin II, the Empress Sophia.

Alboin, faced with the possibility of annihilation, makes an alliance in 566 with the Avars under Bayan I, at the expense of some tough conditions; the Avars demand a tenth of the Lombards' cattle, half of the war booty, and on the war's conclusion all of the lands held by the Gepids.

The Lombards play on the pre-existing hostility between the Avars and Constantinople, claiming that the latter is allied with the Gepids.

Cunimund, on the other hand, encounters hostility when he once again asked the Emperor for military assistance, as Constantinople has been angered by the Gepids' failure to cede Sirmium to the empire, as had been agreed.

Moreover, Justin II is moving away from the foreign policy of Justinian, and believes in dealing more strictly with bordering states and peoples.

Attempts to mollify Justin II with tributes fail, and as a result the Empire remains neutral if not outright supportive of the Avars.

The refusal of Justin II to continue the payment of tribute to Avar or Persian preserves the resources of the treasury, which he further increases by levying new taxes.

Praiseworthy as his refusal to submit to blackmail may seem, Justin's intransigence only increases the menace to the empire.

John III, patriarch of Constantinople, organizes a compromise between the Chalcedonians and Monophysites.

Cunimund makes the same offer to Justin II as he had before, and this time when Justin accepts, the Gepid king hands Sirmium over to the Empire.

As it turns out, however, the imperial troops neglect to join the Gepids in their fight but keep Sirmium, and although the Avars do not show up either, the Lombards soundly defeat Cunimund in 567, crushing their foes in a pincer movement.

According to the writings of Paul the Deacon, Alboin killed the defeated king and had his skull converted into a drinking cup known as a scala or patera.

The Avars now conquer Transylvania, and the surviving Gepidae are hereafter absorbed into the Lombard nation or become submerged in Avar domains.

Emperor Justin II, despite an alliance with the Franks, is unable to prevent the Lombards from entering Italy in 568, and parts of that country are soon permanently lost to the Roman Empire.

Similar, though less serious, reverses mark Justin's relations with the Avars and Persians.

Shortly after his accession, determined to abandon Justinian's policy of buying peace, he had rejected an Avar request for tribute.

In 568, he concludes an alliance with the Western Turks of Central Asia, apparently directed against the Avars and Persians.