The actual name of the dynasty is not known. Cometopuli (Bulgarian: , ; Byzantine Greek: , ) is merely the nickname which is used by Byzantine historians to address rulers from the dynasty as its founder, Nicholas, was a "komes" (governor, cognate to "count"; Byzantine Greek: , , from the Latin "comes"; Bulgarian: , ) either of the region of Sredets (the present-day capital of Bulgaria, Sofia) or of the region of Prespa. According to the 11th century Armenian historian, Stepanos Asoghik, the dynasty was of Armenian origin. In 969 AD and following the Russo-Byzantine conquest of Eastern Bulgaria, count Nikola assumed control of the Bulgarian lands west of the rivers Iskar and Struma. By the time of the Byzantine conquest of Preslav and the dethronement of Tsar Boris II in 972, Nikola had been killed and the rule assumed by his four sons, David, Aaron, Moses, and Samuil. David led the defence of southwestern Bulgaria and resided in Prespa, Moses of southeastern Bulgaria residing in Strumica, Aaron ruled over the region of Sredetz, whereas Samuel was in charge of northern Bulgaria with the town of Bdin (Vidin).