The so-called 'social revolutions' following the independence proclamation were challenges to the Dutch-established Indonesian social order, and to some extent a result of the resentment against Japanese-imposed policies. Across the country, people rose up against traditional aristocrats and village heads and attempted to exert popular ownership of land and other resources. The majority of the social revolutions ended quickly; in most cases the challenges to the social order were quashed, although in East Sumatra, the sultanates were overthrown and there were mass killings of members of the aristocratic families.