This is known as the system of _Appanages_.
To his son Yaropolk he gave Kief, to Oleg the territory of the Drevlians, and to Vladimir Novgorod.

But as Vladimir quickly assassinated Yaropolk, who had already assassinated Oleg, the injurious results of the system were not directly felt! Vladimir became the sole ruler.

He then started upon a course of unbridled profligacy.

He compelled the widow of his murdered brother to marry him--then a beautiful Greek nun who had been captured from Byzantium--then a Bulgarian and a Bohemian wife, until finally his household was numbered by hundreds.

But this sensual barbarian began to be conscious of a soul.