Khan Kubrat, having established a spacious state in the steppes of modern Ukraine, has ruled in peace with Constantinople, a result of his close friendship with the emperor and, conceivably, of his appreciation of the Empire’s culture.

According to legend the third, fourth, and fifth of the many sons of Kubrat with their hordes originally inhabited the Avar Khaganate.

The Pereshchepina hoard, discovered in 1912 by Ukrainian peasants in the vicinity of Poltava, yielded gold and silver objects of total weight of seventy-five kilograms, including a ring which eventually allowed identification of the grave as that belonging to Khan Kubrat.

The ring was inscribed in Greek "Chouvr(á)tou patr(i)k(íou)", indicating the dignity of patrikios that he had achieved in Constantinople.

His eldest son Batbayan succeeds Kubrat in Onoguria in 665.

Bulgar khan Batbayan, warring with his relative Kotrag in 668, is temporarily driven into the Crimea.

Kotrag’s Khazars attack and eventually take the steppes between Don and the Urals, according to the treaty of 668 between Batbayan and the Khazar Khagan (Kaban) under which Batbayan and his sister Huba are taken prisoners.

Western Bulgar warriors will later adopt the practice of wearing Martenitsas—a small piece of adornment, made of white and red yarn and usually in the form of two dolls, a male and a female—in battle to remind them of the sacrifice of their ancestral relatives Batbayan and Huba.

Batbayan's Bulgars are an essential part of the ethnogenesis of the contemporary Balkars and probably in some scale of the Volga Tatars and Crimean Tatars, though the ethnogenesis of the eponymous inhabitants of modern Bulgarian is probably very little influenced by Batbayan's Bulgars.

When Great Bulgaria disintegrates under Khazar attack in 668, Batbayan's brothers part ways, leading their people to seek a more secure home in other lands.

Khan Kubrat’s five sons split the Bulgar people into five hordes, according to Greek sources.

One of these five, remaining on the coast of the Sea of Azov, is absorbed into the new empire of the Khazars.

Two of the five Bulgar hordes are to have longer futures.

Kubrat's son Bezmer, or Batbayan, avoids the Khazars by leading his horde far to the north, where it eventually occupies an ill-defined country around the confluence of the Volga and Kama rivers.

Subdivided here into three groups (probably through mergers with indigenous peoples or with other immigrants), the horde will maintain itself in prosperity for some six hundred years.

Asparukh, one of the sons of Kubrat, is followed by thirty thousand to fifty thousand Bulgars.

He reaches the Danube and, while the imperial capital, Constantinople, is besieged by Muawiyah I, Caliph of the Arabs (674–678), he and his people settle in the Danube delta, probably on the now disappeared Peuce Island.