Accession to the throne thumb|Romanos IV pictured in the 15th century Codex Mutinensis graecus. Romanos Diogenes was the son of Constantine Diogenes and a member of a prominent and powerful Byzantine Greek family from Cappadocia, the Diogenai,Norwich 1993, p. 344 connected by birth to most of the great aristocratic nobles in Asia Minor.Finlay 1854, p. 30 His mother was a daughter of Basil Argyros, brother of the emperor Romanos III.Cheynet & Vannier 2003, p. 78. Courageous and generous, but also impetuous, Romanos rose with distinction in the army due to his military talents, and he served in Syria and on the Danubian frontier.Kazhdan 1991, p. 1807 At that time some parts from the theme of Bulgaria were organized as a new province with the centre at Serdica, and he became a duke of that province in 1067.Alexandru Madgearu, Ruled indeed Basil Apokapes the Paradunavon Theme?, "Acta Musei Varnensis", 3 (The Bulgarian Lands in the Middle Ages, 7th–18th Centuries. International Conference. A tribute to Prof. Alexander Kuzev's 70th anniversary, Varna, 12–14 September 2002), Varna, 2005, pp. 273–282. However, he was eventually convicted of attempting to usurp the throne of the sons of Constantine X Doukas in 1067. While waiting to receive his sentence from the regent Eudokia Makrembolitissa, he was summoned into her presence and advised that she had pardoned him and that she had furthermore chosen him to be her husband and the guardian of her sons as emperor.Finlay 1854, p. 29 She took this course of action primarily due to her concern that unless she managed to find a powerful husband, she could easily lose the regency to any unscrupulous noble, and also because she was infatuated with the popular Romanos. Her decision was met with little protest as the Seljuk Turks had overrun much of Cappadocia and had even taken the important city of Caesarea, meaning that the army needed to be placed under the command of an able and energetic general.
accession to the throne thumb|romanos iv pictured in the 15th century codex mutinensis graecus romanos diogenes was the son of constantine diogenes and a member of a prominent and powerful byzantine greek family from cappadocia the diogenainorwich 1993 p 344 connected by birth to most of the great aristocratic nobles in asia minorfinlay 1854 p 30 his mother was a daughter of basil argyros brother of the emperor romanos iiicheynet & vannier 2003 p 78 courageous and generous but also impetuous romanos rose with distinction in the army due to his military talents and he served in syria and on the danubian frontierkazhdan 1991 p 1807 at that time some parts from the theme of bulgaria were organized as a new province with the centre at serdica and he became a duke of that province in 1067alexandru madgearu ruled indeed basil apokapes the paradunavon theme "acta musei varnensis" 3 (the bulgarian lands in the middle ages 7th–18th centuries international conference a tribute to prof alexander kuzev's 70th anniversary varna 12–14 september 2002) varna 2005 pp 273–282 however he was eventually convicted of attempting to usurp the throne of the sons of constantine x doukas in 1067 while waiting to receive his sentence from the regent eudokia makrembolitissa he was summoned into her presence and advised that she had pardoned him and that she had furthermore chosen him to be her husband and the guardian of her sons as emperorfinlay 1854 p 29 she took this course of action primarily due to her concern that unless she managed to find a powerful husband she could easily lose the regency to any unscrupulous noble and also because she was infatuated with the popular romanos her decision was met with little protest as the seljuk turks had overrun much of cappadocia and had even taken the important city of caesarea meaning that the army needed to be placed under the command of an able and energetic general