The Australian National University Act established a national research institution in 1946. The first Vice-Chancellor, Professor Sir Douglas Copland, was appointed in 1948, and the research schools were established with academic staff, many recruited from overseas, and postgraduate students. See the History of the ANU for a timeline and more detail.
There are several predecessors to the University:
The ANU Archives exhibition, Building Australia's National University: 75 Years of the Australian National University outlines and illustrates the history of the campus and many of its buildings. This is a valuable reference for where ANU staff and students studied, worked, lived and socialised.