Spāhbed (Middle Persian: 𐭮𐭯𐭠𐭧𐭯𐭲; early form spāhpat) is a Middle Persian title meaning "army chief" used chiefly in the Sassanid Empire. Originally there was a single spāhbed, called the Ērān-spāhbed, who functioned as the generalissimo of the Sassanid army. From the time of Khosrau I (r. 531–579) on, the office was split in four, with a spāhbed for each of the cardinal directions. After the Muslim conquest of Persia, the spāhbed of the East managed to retain his authority over the inaccessible mountainous region of Tabaristan on the southern shore of the Caspian Sea, where the title, often in its Islamic form ispahbadh (Persian: اسپهبذ; Arabic form اصبهبذ işbahbadh), survived as a regnal title until the Mongol conquests of the 13th century.
The title was also adopted by the Armenians ([a]sparapet) and the Georgians (spaspeti), as well as Khotan (spāta) and the Sogdians (spʾdpt) in Central Asia. It is also attested in Greek sources as aspabedēs (ἀσπαβέδης).
The title was revived in the 20th century by the Pahlavi dynasty, in the New Persian form sepahbod (Persian: سپهبد), equivalent to a three-star Lieutenant General, ranking below arteshbod (full General). An equivalent title, spāhsālār, gained great currency across the Muslim world in the 10th–15th centuries.
Use in pre-Islamic Persia 
The title is attested in the Achaemenid Empire in its Old Persian form, spādhapati (from *spādha- "army" and *pati- "chief"), signifying the army's commander-in-chief. The title (Parthian: 𐭎𐭐𐭀𐭃𐭐𐭕𐭉) continued in use under the Arsacid Parthian Empire, where it seems to have been a hereditary position in one of the seven great houses of the Parthian nobility.
The Sassanid Empire, which succeeded the Arsacids, retained the title, which is attested in a series of inscriptions from the 3rd century. Until the early 6th century, there was a single holder of the title, the Ērān-spāhbed, who according to the list of precedence provided by the 9th-century Arab historian Ya'qubi occupied the fifth position in the court hierarchy.
The Byzantine and Syriac sources record a number of senior officers who might be holders of the rank in the early 6th century. Thus during the Anastasian War of 502–506, a certain Boes, who negotiated with the Byzantine magister officiorum Celer and died in 505, is named in the Syriac sources as an astabid. His unnamed successor in the negotiations also bore this title. Although this has been interpreted by some modern scholars as a new office, that of astabed, it is likely that this is simply a corrupted form of spāhbed, since the Greek sources give the name of the second man as Aspebedus or Aspetius. Again, during the Iberian War (526–532), a man named Aspebedes, according to the historian Procopius a maternal uncle of Khosrau I (r. 531–579), appears. In 527 he took part in negotiations with Byzantine envoys, and in 531 he led an invasion of Mesopotamia along with Chanaranges and Mermeroes. He was executed by Khosrau shortly after his accession for plotting with other nobles to overthrow him in favour of his brother Jamasp.
Khosrau I's reform 
To curb the power of the over-mighty generalissimo, Khosrau I—although this reform may already have been planned by his father, Kavadh I (r. 499–531)—split the office of the Ērān-spāhbed in four regional commands, corresponding to the four traditional cardinal directions (kust, cf. Šahrestānīhā ī Ērānšahr): the "army chief of the East (Khurasan)" (kust ī khwarāsān spāhbed), the "army chief of the South" (kust ī nēmrōz spāhbed), the "army chief of the West" (kust ī khwarbārān spāhbed), and the "army chief of Azerbaijan" (kust ī Ādurbādagān spāhbed, where the northwestern province of Azerbaijan substitutes the term "north" because of its negative connotations). As this reform was mentioned only in later literary sources, the historicity of this division, or its survival after Khosrau I's reign, was questioned in the past, but a series of thirteen recently discovered seals, which provide the names of eight spāhbeds, provide contemporary evidence from the reigns of Khosrau I and his successor, Hormizd IV (r. 579–590); P. Pourshariati suggests that two may date to the reign of Khosrau II (r. 590–628). The eight known spāhbeds are:
(possibly Khosrau I's minister Burzmihr)
|Wahrām Ādurmāh||South||Khosrau I & Hormizd IV||Unknown|
(possibly the general and usurper Shahrbaraz)
|South||Khosrau I (or Khosrau II)||Mihrān|
(possibly Vistahm, Khosrau II's uncle)
|West||Khosrau I (or Khosrau II) & Hormizd IV||Ispahbudhān|
|Gōrgōn or Gōrgēn (?)||North||Khosrau I||Mihrān|
|Sēd-hōsh (?)||North||Khosrau I||Mihrān|
Other holders of the rank are difficult to identify from the literary sources, since the office of spāhbed was held in tandem with other offices and titles, such as Shahrwarāz ("Boar of the Empire"), which are often treated as personal names. A further factor of confusion in later literary sources is the interchangeable use of the rank with the junior provincial ranks of marzobān ("frontier-warden, margrave") and pāygōsbān ("district guardian").
Islamic period 
During the Muslim conquest of Persia, the spahbed of Khurasan apparently retired to the mountains of Tabaristan. There he invited the last Sassanid shah, Yazdgerd III, to find refuge, but Yazdgerd refused, and was killed in 651. Like many other local rulers throughout the former Sassanid domains, including those of the neighbouring provinces of Gurgan and Gilan, the shahbed then made terms with the Arabs, which allowed him to remain as the practically independent ruler of Tabaristan in exchange for an annual tribute. This marked the foundation of the Dabuyid dynasty, which ruled Tabaristan until 759–761, when it was conquered by the Abbasids and incorporated into the Caliphate as a province. The early rulers of the dynasty are ill attested; they minted coins of their own with Pahlavi legends and a dating system starting from the Sassanid dynasty's fall in 651, and claimed the titles Gīlgīlan, Padashwargarshah ("Shah of Patashwargar", the old name of Tabaristan's mountains), and ispahbadh (a New Persian form of spahbed) of Khurasan.
The title ispahbadh was also claimed by other lines of local rulers in the region, who claimed distant descent from the Sassanid past: the Qarinwand family, who saw themselves as heirs of the Dabuyids and ruled central and western Tabaristan until 839/840, and the Bavandid dynasty in the eastern mountains, whose various branches survived until well after the Mongol conquests of the 13th century. The title was also used by the Daylamites neighbouring Tabaristan. In some later texts from this region, the title came to signify simply a local chieftain.
Central Asia 
In Khurasan, the title survived in usage among the local Soghdian princes. The ispahbadh of Balkh is mentioned in 709, al-Ishkand, the ispahbadh of Nasa in 737, and the same title is used in connection with the king of Kabul in the early 9th century. In the 1090s, it appears as the personal name of a Seljuk commander, Isfabadh ibn Sawtigin, who seized control of Mecca for a while.
In Armenia 
The Kingdom of Armenia, which was ruled by a branch of the Parthian Arsacid dynasty, adopted the term first in its Old Persian form, giving Armenian [a]parapet and then again, under Sassanid influence, from the Middle Persian form, giving the form aspahapet. The title was used, as in Persia, for the commander-in-chief of the royal army, and was borne in hereditary right by the Mamikonian family.
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