 In 842, during the reign of Khan Presian I, the region became part of the First Bulgarian Empire.During the Christianization of Bulgaria under Presian's son Boris I, Kutmichevitsa became one of the two most important cultural centers of Bulgaria, the other being the original core of the Bulgarian state around Pliska and Preslav.The Ohrid Literary School produced many works important for the Medieval Bulgarian literature as well as for all the Slavic peoples.