Anthemius in the context of "Anthemiolus"

The Leonid dynasty or Thracian dynasty produced six Byzantine emperors during Late Antiquity, reigning over the Byzantine Empire from 457 to 518. The dynasty's patriarch was Leo I, who was made Byzantine emperor in 457. Leo's daughter Ariadne became empress and mother to an emperor, and her two husbands were themselves each made emperor in turn. Another relative whose name does not survive of Leo I or his wife Verina married the future augustus Julius Nepos (r. 474–480), the last emperor in the Western Roman Empire. The dynasty of Leo succeeded the preceding Valentinianic dynasty (r. 364–455) and Theodosian dynasty (r. 379–457) whose family trees were conjoined and ruled concurrently. Besides Julius Nepos, who administered no more than a rump state the Roman province of Dalmatia in the western empire during the fall of the west, the dynasty's emperors governed the Byzantine Empire (east).

Leo's eldest daughter Ariadne married Zeno, and their son, Leo II was proclaimed augustus and succeeded his grandfather Leo as an infant, appointing Zeno co-augustus. Leo's younger daughter, Leontia, married first the caesar Patricius, son of the magister militum Aspar, and then Marcianus, son of the augustus Anthemius (r. 467–472). When Leo II died in the year of his grandfather's death, Zeno remained augustus in the Byzantine Empire.

The Visigothic Kingdom, Visigothic Spain or Kingdom of the Goths (Latin: Regnum Gothorum) was a barbarian kingdom that occupied what is now southwestern France and the Iberian Peninsula from the 5th to the 8th century. One of the Germanic successor states to the Western Roman Empire, it was originally created by the settlement of the Visigoths under King Wallia in the province of Gallia Aquitania in southwest Gaul by the Roman government and then extended by conquest over all of Hispania. The Kingdom maintained independence from the Eastern Roman or Byzantine Empire, whose attempts to re-establish Roman authority in Hispania were only partially successful and short-lived.

The Visigoths were romanized central Europeans who had moved west from the Danube Valley. They became foederati of Rome, and sought to restore the Roman order against the hordes of Vandals, Alans and Suebi. The Western Roman Empire fell in 476 AD; therefore, the Visigoths believed they had the right to take the territories that Rome had promised in Hispania in exchange for restoring the Roman order. Under King Euric—who eliminated the status of foederati—a triumphal advance of the Visigoths began. Alarmed at Visigoth expansion from Aquitania after victory over the Gallo-Roman and Breton armies at Déols in 469, Western Emperor Anthemius sent a fresh army across the Alps against Euric, who was besieging Arles. The Roman army was crushed at the nearby Battle of Arles, resulting in Euric capturing Arles and secured much of southern Gaul.

Julius Nepos (died 9 May 480), or simply Nepos, ruled as Roman emperor of the West from 24 June 474 to 28 August 475. After losing power in Italy, Nepos retreated to his home province of Dalmatia, from which he continued to claim the western imperial title, with recognition from the Eastern Roman Empire, until he was murdered in 480. Though Nepos' successor in Italy, Romulus Augustulus (r. 475–476), is traditionally deemed the last western Roman emperor, Nepos is regarded by some historians as the true last emperor of the west, being the last widely recognised holder of the position.

A native of Dalmatia, Nepos began his career as the semi-autonomous governor of the province, succeeding his uncle Marcellinus, a prominent general, as magister militum ('master of troops') of Dalmatia. After the death of the western emperor Anthemius (r. 467–472), who had been appointed by the eastern emperor Leo I (r. 457–474), as well as Anthemius' successor Olybrius (r. 472), Leo sought to assert his authority in the west, granting Nepos command of an army in December 473 to attack Italy and depose Glycerius (r. 473–474), who had been proclaimed emperor by the Burgundian general Gundobad. Nepos left for Italy in the spring of 474, backed by Leo's successor Zeno, and landed with his army at Portus, near Rome. Nepos swiftly deposed Glycerius and was crowned western emperor in Rome on 24 June 474. He was the last emperor to be crowned in the city until Charlemagne in the ninth century. Whether the original intention of the invasion was to install Nepos as western emperor is unclear, but in any event, he was quickly recognised as the legitimate western emperor by Zeno.

Flavius Marcianus (Greek: Μαρκιανός, fl. AD 469–484) was a member of the Leonid dynasty. The son of the Western emperor Anthemius, Marcianus married Leontia, the daughter of the Eastern Roman emperor Leo I. He was consul twice, and in 479 unsuccessfully attempted to overthrow the emperor Zeno. After his capture he was forced to become a monk; he escaped and raised an army but was defeated and recaptured by Flavius Appalius Illus Trocundes. In 484, when the Isaurian general Illus revolted against Zeno, Marcianus was freed and Illus proclaimed him emperor, before deposing him in favour of Leontius.

The Battle of Arles was fought between the Visigoths and the Western Roman Empire in 471. Prior to the battle, the Visigoths had advanced past the Bretons at the Battle of Déols in 469, and were expanding into Aquitaine. Alarmed with this development, Emperor Anthemius sent an expedition under Anthemiolus across the Alps against the Visigothic king Euric, who was besieging Arles. Euric crushed the Roman army and killed Anthemiolus and three Roman counts. Euric subsequently captured Arles and much of southern Gaul. The defeat in Gaul was a direct cause of the subsequent overthrow of Anthemius as emperor by Ricimer.

Marcia Euphemia, also known as Aelia Marcia Euphemia (Greek: Μαρκία Εύφημία), was the wife of Anthemius, Western Roman Emperor.