Roman is the second surviving son of Emperor Peter I of Bulgaria by his marriage with Maria (renamed Eirene) Lekapene, the granddaughter of the Emperor Romanos I Lekapenos.
It is possible that he had the double name Roman-Simeon, but this may be due to confusion with another man in the sources.
He was born around 930, and had probably visited Constantinople with his mother and older brothers soon after 931.
We know nothing about Roman's life until 968, when he joined his older brother Boris in Constantinople to negotiate a peace agreement between Bulgaria and the Empire, during which they apparently served as honorary hostages at the imperial court.
On their father's abdication in 969, Boris and Roman had returned to Bulgaria, where Boris II had succeeded as emperor.
Roman may have been proclaimed co-emperor in accordance with imperial Greek usage, but the evidence for that is vague.
In Bulgaria, Roman probably had shared his brother's destiny, becoming first a pawn in the hands of Prince Sviatoslav I of Kiev and then in those of the Emperor John I Tzimiskes.
After the latter's victory in 971, Roman had been taken to Constantinople together with his brother's family.
To ensure that the Bulgarian royal dynasty will die out (Boris II apparently has only daughters), the emperor has Roman castrated.
Boris and Roman had remained in honorary captivity at the imperial palace until after the death of the emperor in 976.
At this point the raids of the Kometopouloi into Constantinople’s possessions in Macedonia lead to an imperial stratagem intended to divide the leadership of the still-unconquered Bulgarian lands in the west.
After the Empire’s plan to use Aaron to cause instability in Bulgaria fails, they try to encourage the rightful heirs to the throne, Boris II and Roman, to oppose Samuel.
Basil II hopes that they will win the support of the nobles and isolate Samuel or perhaps even start a Bulgarian civil war.
Temporarily jailed, Boris and Roman are allowed to escape in 977.
During their attempt to cross the Bulgarian border, Boris II is taken for an enemy and killed by a guard who had been misled by Basil’s clothing.
Roman, who is walking some distance behind, manages to identify himself to the Bulgarian patrols, and is taken to Vidin, where he is proclaimed Emperor of Bulgaria.
Samuel becomes his first lieutenant and general and together they gather an army to fight the Empire.
Samuel is certain to eventually succeed Roman.
The new emperor entrusts Samuel with the state administration and becomes occupied with church and religious affairs.
