Question

How did social interactions allow the fujiwara to gain power in Japan's government

Answer 1

through the marriage of Fujiwara daughters to emperors. It meant that the Fujiwara daughters were empresses, that their grandsons and nephews were emperors, and that members of their family, including its lesser branches, received all the patronage. Thus, the Fujiwara clan chieftain, whether he held office or not, could manipulate the reins of government.