The basilica was built at the place of what is known as the cross-shaped Mausoleum, an older religious building that is thought by some researchers to be an unknown kind of Bulgar heathen temple.
According to the Shumen architectural museum's research, an early Christian martyrium that included a cross-shaped church and a holy spring also existed at that place.
Two necropoleis are located in the vicinity of the complex: a monastic necropolis lies to the southwest of the church, while a secular one intended for nobles was unearthed in front of the basilica's apse.
[3] By the early 9th century, Pliska was surrounded by a defensive wall and 2,300 hectares (5,700 acres) of land was further enclosed by an outer earthwork with stone revetment 21 kilometres (13 miles) long.
[2] After the Byzantine army sacked and burned Pliska in 811, led by the emperor Nikephoros I (r. 802–811), Pliska was rebuilt by Omurtag (r. 814–831), who used spolia from nearby Roman buildings and employing late Roman-inspired rectilinear and basilica plans in the architecture of his new ashlar palace, which descended from Late Antique prototypes like Diocletian's Palace at Split, Croatia.