The following investigation stems from a desire to explain narrative reliefs from the so-called Amaravati School, i.e. the Buddhist sites in Andhra Pradesh (1st c. BC and4th c. AD). Seemingly, the reliefs from this school should be related to textual sources preserved in 'northern' Buddhism due to numerous scenes having no counterpart in Pali literature. As still many reliefs are left unexplained, an attempt should be made to establish school affiliations of the monasteries in which the reliefs were unearthed, with reference to the largest excavation site in the region, Nagarjunakonda, the ancient Vijayapurī of the Iksvāku.
Inscriptions provide us with information about four Iksvāku kings, ruling in the valley between approx. 210 and 310. Vijayapurī had been founded earlier by the Sātavāhans to whom the Iksvāku were subordinated. When independent, the local dynasty tried to imitate the great Sātavāhanas from Dharanikota, approx. 125 km downstream, in the vicinity of which stands the stūpa known today as Amaravati. The Buddhism must have been very important, since there were nearly 40 Buddhist sites in the close vicinity of Vijayapurī. All those monasteries existed side by side, maintaining different architectural forms.
The monasteries with stūpas without the āyaka-projections seem to belong to traditional schools; in two such establishments inscriptions were found connecting them with the Mahāvihāravāsins, the Theravāda-Vibhajyavāda school from Ceylon. The site 7/8, whose inscription connects it with the Mahīśāsakas, had stūpas with āyakasbut no apsidal temple. Another monastic community known from the inscription belonged to the Bahuśrutīyas. Two apsidal temples facing each other and containing stūpas are most characteristic features of this monastery. Interestingly, site 4 (without any inscription) also had two apsidal temples but none of them had inside a stūpa.