Prior to Kubrat:
Attila the Hun. Image source: Wikipedia, public domain.
Dengizich (died 468 or 469) (Hunnic Ruler) was a son of Attila the Hun. Some time during his reign, the Unogurs (Onogurs) first crossed the river Volga.
Ernakh or Ernac was the 3rd son of Attila. After Attila's death in 453 AD, his empire crumbled and its remains were ruled by his three sons. Ernakh succeeded Dengizich and reigned from 469 AD to 503 AD over the Huns who roamed a substantial part of the former empire and inhabited the lands of modern Ukraine. Ernakh managed to assert himself as ruler of also the Bulgar Onogurs who had come upon the Acatzir Huns in 463 during the preceeding reign of his brother Dengizich. According to the Nominalia of the Bulgarian khans, a ruler named Irnik was a leader of the Bulgars for 150 years and his reign began approximately in 453 AD. Some historians consider Ernakh and Irnik to have been the same person.
Utigur (ruled 503-520) was one of two sons of Ernakh whose name certain Bulgars adopted.
Grod (c. 520-528) visited Constantinople, converted to Christianity and began to suppress the native cults. Grod's nobles overthrew and murdered him and replaced him with his brother Mugel.
Mugel was the successor of Grod (or Grodas), a Hunnic ruler, whose reign lasted only 2 years, from AD 528 to 530.
Sandilch, 555, was promoted as Khan of the Utigur Bulgars in Patria Onoguria and an ally to the Byzantines.
Houdbaad (c. 584-c. 600). After his death Organa became regent of until Kubrat was old enough to lead them.
Organa (Bu-Yurgan) was Kubrat's maternal uncle of the Ermy clan. He was regent over the tribe of the Onogur Bulgars from 617 to 630 in place of his nephew, Kubrat, for the time Kubrat was growing up as a hostage in the Byzantine Empire.
Gostun was a regent over the Bulgars for 2 years. It is possible that Gostun is an alternative name of Organa, who was a regent over the Bulgars until Kubrat's return from Constantinople.
Kubrat or Kurt ("Rebel-father"; Bulgarian: Кубрат) was a Bulgar ruler credited with establishing the confederation of Old Great Bulgaria in 632. He is said to have achieved this by conquering the Avars and uniting all the Bulgar tribes under one rule.
Kubrat spent time at the Byzantine court, either as a hostage or for protection from a dynastic war.
Whether he was a child or an adult during his time in Constantinople is unclear, as the year of his birth is unknown. The exact time of this event is also unknown but probably coincided with the reign of Emperor Heraclius (610-641). If the above text really applies to Kubrat then it becomes clear that during his stay in Constantinople he was educated and baptized. Probably at the same time he was given the title Patrician, which was inscribed on his ring.
Upon return, Kubrat took power over his tribe, the Utigur Bulgars, from Organa who had acted as regent until then. Kubrat expelled the Avar troops from his lands and ruled singlehandedly over the united Bulgars thus creating the Great Bulgaria. Under his rule the Old Great Bulgaria grew to stretch from the Danube delta to the Volga river, and was recognized by an international treaty signed with Byzantium in 635. Kubrat ruled in peace with the Byzantine Empire, a result of his close friendship with the Byzantine emperor and of his appreciation of Byzantine culture.
In 1912, Ukrainian peasants in the vicinity of Poltava stumbled over a gravesite replete with magnificent gold and silver objects of total weight of 75 kg, including a ring which eventually allowed identification of the grave as that belonging to Khan Kubrat.
Offspring: Batbayan, Kotrag, Asparukh, Altsek, Kuber (possibly).
Batbayan (died 690) (also known as Bayan or Boyan, Bezmer) was the eldest son of Khagan Kubrat. In 668, Batbayan engaged in a war with his relative Cozrig and eventually Batbayan and his sister Huba were taken prisoners. Western Bulgar warriors adopted the practice of wearing Martenitsas in battle to remind them of the sacrifice of their ancestral relatives Batbayan and Huba.
Rulers of Danube Bulgaria of the Dulo dynasty:
Simeon I the Great
Batbayan of Bulgaria. Wikipedia.
Dulo clan. Wikipedia.