Article: As culture flourished, so did decentralization. Whereas the first phase of shōen development in the early Heian period had seen the opening of new lands and the granting of the use of lands to aristocrats and religious institutions, the second phase saw the growth of patrimonial "house governments," as in the old clan system. (In fact, the form of the old clan system had remained largely intact within the great old centralized government.) New institutions were now needed in the face of social, economic, and political changes. The Taihō Code lapsed, its institutions relegated to ceremonial functions. Family administrations now became public institutions. As the most powerful family, the Fujiwara governed Japan and determined the general affairs of state, such as succession to the throne. Family and state affairs were thoroughly intermixed, a pattern followed among other families, monasteries, and even the imperial family. Land management became the primary occupation of the aristocracy, not so much because direct control by the imperial family or central government had declined but more from strong family solidarity and a lack of a sense of Japan as a single nation.

Question: Succession to the throne was determined by what clan?
Fujiwara