Arsaber is shown in a number of secondary sources as the son of Narses (or Nerses) IV Kamsarakan, Prince of Shirak. However, to-date I have found no historical research to advance this claim.
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KAMSARAKAN, Armenian noble family that was an offshoot of the Kāren Pahlav, one of the seven great houses of Iran claiming Arsacid origin. The Kamsarakans reigned in two princely states, both situated in the region of Ayrarat (Ararat)-Aršarunikʿ, with the old Armenian capital of Eruandašat as their capital and with the fortresses of Bagaran (presend-day Pakran) and Artagers (Artogerassa), and Širak (Sirakenē) with the fortress (and later city) of Ani. The family’s chief name was derived from Prince Kamsar, who died in 325;... after the 8th century, it bore, in memory of its origin, the surname of Pahlavuni. Enjoying from the beginning the prestige of being the cousins of the royal Arsacids (Movsēs Xorenacʿi, 2.72, 90), the Kamsarakans also acquired, after the downfall of the Arsacids in 428, a considerable political weight owing to their quasi-margravial position on the northern frontier of the realm. Of the four broad classes in the relative precedence of the Armenian princes, the Kamsarakans can be placed in the second, and the feudal aid they were expected to render to their suzerain, the king of Armenia, was fixed at 600 horses.
The geographical situation of its principalities prevented this house from being in any special way involved in Armino-Iranian relations. Upon the Roman annexation of the west Arminian kingdom in 390, Gazavon II Kamsarak, hitherto the leader of the pro-Roman princes, moved, together with some of them, to the side of the Iranian vassal, the king of east Armenia. On the other hand, the Kamsarakans, under Aršavir II, took part in the anti-Iranian insurrection of 451 and, again with his son and successor Narses, in that of 482-84. On the whole they followed a pro-Byzantine policy and took an active part in the life of that empire. Three Kamsarak brothers were generals in the imperial service under Justinian I: Narses, duke (dux) of the Thebais, Aratius or Hrahat, duke of Palestine (Adontz, pp. 164, 447-48), and Sahak (Isaac), executed by Totila, the king of Ostrogoths, in 546. Another Isaac, who appears to have been a member of the Kamsarakan family, was imperial exarch of Italy in 625-43. Narses II Kamsarakan was the presiding prince of Armenia for the emperor in the years 689/90-691 and held the high Byzantine position of curopalate; and another presumable Kamsarak, the patrician Arsaber or Aršavir, rose against the emperor in 808.... 1
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In February 808 a plot was formed to dethrone Nicephorus by a large number of discontented senators and ecclesiastical dignitaries.... [The] man who was designated by the conspirators to be the new Emperor was on this occasion an Armenian. The patrician Arsaber held the office of Quaestor; and the chronicler, who regarded with favour any antagonist of Nicephorus, describes him as pious. The plot was detected; Arsaber was punished by stripes, made a monk and banished to Bithynia; the accomplices, not excepting the bishops, were beaten and exiled. 2
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The conspiracies which were formed against Nicephorus cannot be admitted as evidence of his unpopularity, for the best of Byzantine monarchs were as often disturbed by secret plots as the worst.... It is only from popular insurrections that we can judge the sovereign's unpopularity. The principles of humanity that rendered Nicephorus averse to religious persecution, caused him to treat conspirators with much less cruelty than most Byzantine emperors. Perhaps the historians hostile to his government have deceived posterity, giving considerable importance to insignificant plots, as we see modern diplomatists continually deceiving their courts by magnifying trifling expressions of dissatisfaction into dangerous presages of widespread discontent. In the year 808, however, a conspiracy was really formed to place Arsaber—a patrician, who held the office of quaestor, or minister of legislation—on the throne. Though Arsaber was of an Armenian family, many persons of rank were leagued with him; yet Nicephorus only confiscated his estates, and compelled him to embrace the monastic life. 3
Greek: Arsaber