The first holder of the office of Domestic of the Schools first appears in the sources (the chronicle of Theophanes the Confessor) for the year 767, shortly after the creation of the tagmata. These were elite cavalry regiments stationed in or around the capital Constantinople, commanded by officers titled "Domestics" (δομέστικοι, domestikoi) and distinct from the provincial armies of the themes under their respective stratēgoi. The Schools (Latin: scholae; Greek: σχολαὶ, scholai) was the senior tagma, tracing their origin to the Scholae Palatinae established by Constantine the Great (reigned (r.) 306–337) and originally placed under the command of the magister officiorum. The historian J.B. Bury has traced a reference to a certain Anianos, "Domestic of the magister", in the Chronicon Paschale for the year 624, and considers this official to be the predecessor of the Domestic of the Schools. As the magister officiorum was gradually deprived of some of his functions in the 7th and 8th centuries, the Domestic apparently became an independent official. The Kletorologion of 899 lists his subordinate officials as comprising his deputy or topotērētēs (τοποτηρητής), the secretary or chartoularios (χαρτουλάριος), the head messenger or proximos (πρόξιμος) and the other messengers (μανδάτορες, mandatores), as well as the various subordinate officers of the regiment (cf. the article on the Scholae Palatinae).
In the 9th century, the office of the Domestic, or "Domesticate" (δομεστικάτον, domestikaton), of the Schools rose in importance and its holder was often appointed as the head of the army in the absence of the emperor. However, this role was not yet enshrined: it depended rather on the abilities of the current Domestic, and other generals of inferior rank were sometimes entrusted with supreme command instead. The Domestic of the Schools nevertheless rose to such prominence that the sources frequently speak of the office as "the Domestic" without further qualification, and the power and influence of the post saw it frequently occupied by persons closely related to the emperor. From the time of Michael III (r. 842–867) on, the Domestic ranked in the imperial hierarchy above all other military commanders except for the stratēgos of the Anatolic Theme. In practice, he quickly became senior even to the latter, as demonstrated by the fact that military leaders like Nikephoros Phokas and John Tzimiskes were promoted from the generalship of the Anatolics to the Domesticate.
In the reign of Romanos II (r. 959–963) the post was split, with a "Domestic of the West" (δομέστικος τῆς δύσεως, domestikos tēs dyseōs) and a "Domestic of the East" (δομέστικος τῆς ἀνατολῆς, domestikos tēs anatolēs) being created for operations in Europe and Asia respectively. The ceremony for the Domestic's appointment is described in the De Ceremoniis (II.3); the same work describes his duties and role in court ceremonies.
With some exceptions, most notably the unparalleled 22-year tenure of John Kourkouas, or in times of domestic instability, Domestics were changed on the average every three to four years. During the 10th century, the Domesticate of the Schools was dominated by members of the Phokas family, which produced six holders of the office. Their attempts to monopolize the office led a series of emperors, concerned over the power of the military aristocracy, to entrust the potentially over-powerful office to non-military court officials, including—especially in the first half of the 11th century, before the military aristocracy reasserted its authority—to eunuchs, even though this was in theory forbidden, with the alternate office of stratopedarches having been created for this purpose.
In the 10th and 11th centuries, the variant "Grand Domestic" (μέγας δομέστικος, megas domestikos) appears sporadically, used in parallel with other variants such as "Grand Domestic of the Schools" or "Grand Domestic of the East/West" for the same person. The Byzantinist Rodolphe Guilland considers most of these early references either as anachronistic references by 12th-century writers, or simply cases where "megas" is used as an honorific prefix, as was the norm with other senior offices during this period, like the Drungary of the Watch or the Domestic of the Excubitors. Nevertheless, Guilland argues that from the time of Alexios I Komnenos (r. 1081–1118) on, the "Grand Domestic" became a separate office, senior to the "plain" Domestics of the Schools and in effect the new commander-in-chief of the army beside the Emperor. However, the usage of the titles is not consistent, and the habitual division of command between East and West seems to have been sometimes applied to the Grand Domesticate as well during the 12th century, causing some confusion as to the nature of the office and its relation to the "plain" Domestic. In the 13th century however the two titles became clearly distinct: the Grand Domestic was the commander-in-chief of the entire army and one of the highest offices of state, while the Domestic of the Schools was relegated to a simple dignity without duties, awarded to provincial governors and other middle-ranking officials. In the words of the mid-14th century Book of Offices of Pseudo-Kodinos, "the Domestic of the Schools once had an office similar to that of the Grand Domestic currently, but he now holds none".
In Pseudo-Kodinos' work, the Domestic of the Schools ranks 31st in the imperial hierarchy, between the mystikos and the Grand Drungary of the Fleet. The Domestic's distinctive court dress, as reported by Pseudo-Kodinos, consisted of a gold-brocaded hat (skiadion), a plain silk kabbadion tunic and a silver staff (dikanikion) with a knob on top and another in the middle. For ceremonies and festivities, he bore the domed skaranikon, of lemon-yellow silk and decorated with gold wire embroidery, and with a portrait of the emperor seated on a throne in front and another with the emperor on horseback on the rear.