An unusual ruler's title, sometimes incorrectly rendered as grand duke, mainly used in Lithuania and some parts of Russia (Muscovy would ultimately unite most Russian principalities and rise to imperial rank) and the Holy Roman Empire.
It had to be divided, therefore, into a number of independent principalities, but it continued to be loosely held together by the dynastic sentiment of the descendants of Rurik and by the patriarchal authority - a sort of patria potestas - of the senior member of the family, called the grand-prince, who ruled in Kiev, " the mother of Russian cities."
What added to the practical difficulties of this arrangement was that the post of grand-prince was not an hereditary dignity in the sense of descending from father to son, but was always to be held by the senior member of the dynasty; and in the subordinate principalities the same principle of succession was applied, so that reigning princes had to be frequently shifted about from one district to another, according as they could establish the strongest claim to vacant principalities.
In these circumstances, the traditional authority of the grand-prince, never very great, rapidly declined, and the complicated law of succession, never scrupulously respected, was gradually replaced by " the good old rule, the simple plan, that he should take who has the power, and he should keep who can."
Yaroslav, surnamed the Great, a man of commanding personality, was the last grand-prince who upheld vigorously the old system.
During these interminable struggles of rival princes, Kiev, which had been so long the residence of the grand-prince and of the metropolitan, was repeatedly taken by storm and ruthlessly pillaged, and finally the whole valley of the Dnieper fell a prey to the marauding tribes of the steppe.