For over a millennium, the Māori, New Zealand's indigenous people, inhabited the banks of the Whanganui River. Uninformed of Western ideas of property ownership, Māori considered the river a sacred ancestor and the source of their ‘ora’, or environmental, social, cultural, economic, physical and spiritual well-being.

As Europeans began to settle in the country, the British Crown proposed a treaty with the Māori. In 1840, the Māori signed the treaty, which had three components: Māori became British subjects; the Crown agreed to safeguard the lands, forests and other treasures of Māori and sovereignty over New Zealand was assumed by the British Crown. Over time, the British government and subsequently the New Zealand government breached parts of the treaty. In the case of the Whanganui River, for example, it was damaged by the removal of minerals and traditional structures from the river and the diversion of the headwaters of the river for hydroelectric production. These and other acts degraded the river and injured its people.

One hundred and seventy-seven years later, the New Zealand parliament conferred personhood on the Whanganui River, using a novel legal theory that was in alignment with the ancient beliefs of the Māori who lived alongside the river. This legislation recognises the interdependence of a river and its people and resolves longstanding grievances by the Māori people against the Crown.