Australian Catholic University (ACU National) was opened on 1 January 1991 following the amalgamation of four Catholic tertiary institutions in eastern Australia - the Catholic College of Education Sydney in New South Wales, the Institute of Catholic Education in Victoria, McAuley College of Queensland, and Signadou College of Education in the Australian Capital Territory.

The institutions that merged to form the University had their origins in the mid-1800s, when religious orders and institutes became involved in preparing teachers for Catholic schools and, later, nurses for Catholic hospitals. Through a series of amalgamations, relocations, transfers of responsibilities and diocesan initiatives, more than twenty historical entities have contributed to the creation of the University.

The University operates as a company limited by guarantee, under the Companies (Victoria) Code and has a constitution which clearly identifies its objects in education, scholarship and research as part of the mission of the Catholic Church.

The University is a member of the publicly-funded national system of Australian universities, the Association of Commonwealth Universities and the International Federation of Catholic Universities. The University's Vice-Chancellor is a member of the Universities Australia and its Board of Directors.