Australia is religiously diverse and increasingly unaffiliated, with the most recent census recording Christians at just under half the population, split between Catholic and various Protestant denominations, religiously unaffiliated Australians now forming the largest single category at close to 40 percent, and Muslim, Buddhist, Hindu and Sikh communities each in the low single digits, figures broadly reflected in Pew Research's Religious Composition of the World, 2010-2020.
Aboriginal Australian religious traditions, encompassing hundreds of distinct language groups and their own cosmologies centered on the Dreaming, an ongoing sacred order linking ancestral creator beings, land and law, represent one of the world's oldest continuous religious traditions, with sites such as Uluru holding deep and specific ceremonial significance to the Anangu traditional owners.
British colonization from 1788 brought Anglican establishment initially, though Australia never developed a formally established national church, and Catholic Irish convict and later free immigration built a substantial Catholic population that historically experienced sectarian tension with the Protestant majority well into the twentieth century. Postwar immigration diversified Australia's religious landscape considerably, adding significant Orthodox Christian, Muslim, Buddhist and Hindu communities from Southern Europe, the Middle East and Asia.