The origin of the early Bulgars (or "Proto-Bulgars") is still unclear.
Their homeland is believed to be situated in Kazakhstan and the North Caucasian steppes.
Interaction with the Hunnic tribes, causing the migration, may have occurred there, but the Pontic–Caspian steppe seems a more likely location.
The first clear mention and evidence of the Bulgars is in the 480s, when they serve as the allies of the Byzantine Emperor Zeno (474–491) against the Ostrogoths.
According D. Dimitrov, the fifth century History of Armenia by Movses Khorenatsi speaks about two migrations of the Bulgars, from Caucasia to Armenia.
The first migration is mentioned in the association with the campaign of Armenian ruler Valarshak (probably Varazdat) to the lands "named Basen by the ancients... and which were afterwards populated by immigrants of the vh' ndur Bulgar Vund, after whose name they (the lands) were named Vanand".
The second migration took place during the time of the ruler Arshak III, when "great disturbances occurred in the range of the great Caucasus mountain, in the land of the Bulgars, many of whom migrated and came to our lands and settled south of Kokh".
Both migrations are dated to the second half of the fourth century.
The "disturbances" that caused them are believed to be the expansion of the Huns in the East-European steppes.
Dimitrov recorded that the toponyms of the Bolha and Vorotan rivers, tributaries of the Aras river, are known as Bolgaru-chaj and Vanand-chaj, and could confirm the Bulgar settlement of Armenia.
The Akatziroi and other tribes that had been part of the Hunnic union were attacked around 463, tby the Šarağurs, one of the first Oğuric Turkic tribes that entered the Ponto-Caspian steppes as the result of migrations set off in Inner Asia.
According to Priscus, in 463 the representatives of Šarağur, Oğur and Onoğur came to the Emperor in Constantinople, and explained they had been driven out of their homeland by the Sabirs, who had been attacked by the Avars.
This tangle of events indicates that the Oğuric tribes are related to the Dingling and Tiele people.
It seems that Kutrigurs and Unigurs arrived with the initial waves of Oğuric peoples entering the Pontic steppes.
The Bulgars were not mentioned in 463.
The eighth-century account by Paul the Deacon in his History of the Lombards says that at the beginning of the fifth century in the northwestern slopes of the Carpathians the Vulgares killed the Lombards’ king Agelmund.
Scholars attribute this account to the Huns; Avars or some Bulgar groups were probably carried away by the Huns to the Central Europe.
When the army of Ostrogoth chieftain Theodoric Strabo grows to thirty-thousand-men strong, it is felt as a menace to Emperor Zeno, who somehow manages to persuade the Bulgars to attack the Thracian Goths.
The Bulgars are in 480/481 defeated, however, by Strabo.
