Fulfilling the Sacred Trust explores the implementation of international accountability for dependent territories under the United Nations during the early Cold War era. Although the Western nations that drafted the UN Charter saw the organization as a means of maintaining the international status quo they controlled, newly independent nations saw the UN as an instrument of decolonization and an agent of change disrupting global political norms. Mary Ann Heiss documents the unprecedented process through which these new nations came to wrest control of the United Nations from the World War II victors that founded it, allowing the UN to become a vehicle for global reform. Heiss examines the consequences of these early changes on the global political landscape in the midst of heightened international tensions playing out in Europe, the developing world, and the UN General Assembly. She puts this anti-colonial advocacy for accountability into perspective by making connections between the campaign for international accountability in the United Nations and other postwar international reform efforts such as the anti-apartheid movement, Pan-Africanism, the Non-Aligned Movement, and the drive for global human rights. Chronicling the combative history of this campaign, Fulfilling the Sacred Trust details the global impact of the larger UN reformist effort. Heiss demonstrates the unintended impact of decolonization on the United Nations and its agenda, as well as the shift in global influence from the developed to the developing world.

Heiss provides the most detailed account available of the 1951 seizure of British oil holdings in Iran by prime minister Mohammed Mossadegh, a turning point in cold war history.