three-naved vaulted basilica, similar to the basilicas of Tekor, Ashtarak and Aparan (Kasagh). However, other scholars, have rejected Sahinian's view. Among them, Suren Yeremian and Armen Khatchatrian held that the original church had been in the form of a rectangle with a dome supported by four pillars. Stepan Mnatsakanian suggested that the original building had been a "canopy erected on a cross [plan]," while architecture researcher Vahagn Grigoryan proposes what Mnatsakanian describes as an "extreme view," that the cathedral has been essentially in the same form as it is today. Reconstruction and decline According to Faustus of Byzantium, the cathedral and the city of Vagharshapat were almost completely destroyed during the invasion of Sasanian King Shapur II in the 360s (circa 363). Due to Armenia's unfavorable economic conditions, the cathedral was renovated only partially by Catholicoi Nerses the Great (r. 353–373) and Sahak Parthev (r. 387–439). In 387, Armenia was partitioned between the Roman Empire and the Sasanian Empire. The eastern part of Armenia where Etchmiadzin was located remained under the rule of Armenian vassal kings subject to Persia until 428, when the Armenian Kingdom was dissolved. In 450, in an attempt to impose Zoroastrianism on Armenians, Sasanian King Yazdegerd II built a fire temple inside the cathedral. The pyre of the fire temple was unearthed under the altar of the east apse during the excavations in the 1950s. By the last quarter of the fifth century the cathedral was dilapidated. According to Ghazar Parpetsi, it was rebuilt from the foundations by marzban (governor) of Persian Armenia Vahan Mamikonian in 483/4, when the country was relatively stable, following the struggle for religious freedom against Persia. Most researchers have concluded that, thus, the church was converted into cruciform church and mostly took its current form. The new church was very different from the original one and "consisted of quadric-apsidal hall built of dull, grey stone containing four free-standing cross-shaped pillars disdained to support a stone cupola." The new cathedral was "in the form of a square enclosing a Greek cross and contains two chapels, one on either side of the east apse." Although the seat of the Catholicos was transferred to Dvin sometime in the 460s–470s or 484, the cathedral never lost its significance and remained "one of the greatest shrines of the Armenian Church." The last known renovations until the 15th century were made by Catholicos Komitas in 618 (according