Dukum

Dukum was probably a brother of the Bulgarian khan Krum (r. 803–814), who might have succeeded Krum as the ruler of Bulgaria for a few weeks or months. After him, the throne was taken by Ditzeng, who died shortly under unclear circumstances. At the end of 814 or early 815 Krum's son Omurtag ascended the throne, thus ending the succession crisis. The circumstances of Dukum's death are unknown and no hypothesis can be ruled out, including a possible involvement of Omurtag himself.

The prevailing scientific thesis had long been that Krum was succeeded directly by Omurtag. Initially, in the 19th and early 20th centuries, a number of scholars, including academician Konstantin Jireček, believed the opposite that, albeit briefly, two or even three monarchs reigned between Krum and Omurtag. According Steven Runciman these may had been only the leaders of rebel factions that for a short while controlled the government at Pliska. Ultimately, the view prevailed that these were military leaders, mistakenly perceived by medieval Byzantine authors as rulers of Bulgaria.