The Kidarite (Chinese: Ki-To-Lo) were a dynasty of the "Ki" clan, probably originating from the Uar people. They were part of the complex of tribes known collectively as Xionites or "Hunas".

During the 4th-5th century they established the Kidarite kingdom.

The Kidarites, a nomadic clan, are supposed to have arrived in Bactria with the great migrations of the second half of the 4th century. When Shi Le established the Later Zhao state, it is thought that many of the Uar from around Pingyang (平陽, in modern Linfen, Shanxi) fled west along the Silk Road. This caused the Xionites to encroach upon Khorasan and the frontiers of the Kushan state around 320 AD.

The Kidarite king Grumbat mentioned by Ammianus Marcellinus was a cause of much concern to the Persians. Between 353 AD and 358 AD, the Xionites under Grumbat attacked in the eastern frontiers of Shapur II's empire along with other nomad tribes. After a prolonged struggle they were forced to conclude a peace, and their king Grumbat accompanied Shapur II in the war against the Romans. Victories of the Xionites during their campaigns in the Eastern Caspian lands are described by Ammianus Marcellinus:

Shapur I or also known as Shapur I the Great was the second Sassanid King of the Second Persian Empire. The dates of his reign are commonly given as 240/42 – 270/72, but it is likely that he also reigned as co-regent (together with his father) prior to his father's death in 242 (more probably than 240).

Shapur was the son of Ardashir I (r. 226–240 [died 242]), the founder of the Sassanid dynasty and whom Shapur succeeded. His mother was Lady Myrōd, who—according to legend—was an Arsacid princess. The Talmud cites a nickname for her, "Ifra Hurmiz", after her bewitching beauty.

Shapur accompanied his father's campaigns against the Parthians, who - at the time - still controlled much of the Iranian plateau through a system of vassal states that the Persian kingdom had itself previously been a part of. Before an assembly of magnates, Ardashir "judged him the gentlest, wisest, bravest and ablest of all his children" and nominated him as his successor. Shapur also appears as heir apparent in Ardashir's investiture inscriptions at Naqsh-e Rajab and Firuzabad. The Cologne Mani-Codex indicates that, by 240, Ardashir and Shapur were already reigning together. In a letter from Gordian III to his senate, dated to 242, the "Persian Kings" are referred to in the plural. Synarchy is also evident in the coins of this period that portray Ardashir facing his youthful son, and which are accompanied by a legend that indicates that Shapur was already referred to as king.

Alexander III of Macedon (20/21 July 356 – 10/11 June 323 BC), commonly known as Alexander the Great (Greek: Ἀλέξανδρος ὁ Μέγας, Aléxandros ho Mégas from the Greek αλέξω alexo "to defend, help" + ανήρ aner "man"), was a king of Macedon, a state in northern ancient Greece. Born in Pella in 356 BC, Alexander was tutored by Aristotle until the age of 16. By the age of thirty, he had created one of the largest empires of the ancient world, stretching from the Ionian Sea to the Himalayas. He was undefeated in battle and is considered one of history's most successful commanders.

Alexander succeeded his father, Philip II of Macedon, to the throne in 336 BC after Philip was assassinated. Upon Philip's death, Alexander inherited a strong kingdom and an experienced army. He was awarded the generalship of Greece and used this authority to launch his father's military expansion plans. In 334 BC, he invaded Persian-ruled Asia Minor and began a series of campaigns that lasted ten years. Alexander broke the power of Persia in a series of decisive battles, most notably the battles of Issus and Gaugamela. He subsequently overthrew the Persian King Darius III and conquered the entirety of the Persian Empire. At that point, his empire stretched from the Adriatic Sea to the Indus River.

Justinian I ( /dʒʌˈstɪniən/) (Latin: Flavius Petrus Sabbatius Iustinianus Augustus, Ancient Greek: Φλάβιος Πέτρος Σαββάτιος Ἰουστινιανός) (c. 482 – 14 November 565), commonly known as Justinian the Great, was Byzantine Emperor from 527 to 565. During his reign, Justinian sought to revive the Empire's greatness and reconquer the lost western half of the classical Roman Empire.

One of the most important figures of Late Antiquity and the last Roman Emperor to speak Latin as a first language, Justinian's rule constitutes a distinct epoch in the history of the Eastern Roman Empire. The impact of his administration extended far beyond the boundaries of his time and domain. Justinian's reign is 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, extending Roman control to the Atlantic Ocean. 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 barbarian control.