Sir William Portus Cullen was Chief Justice of New South Wales between 1910 and 1925. He was the first Australian born Chief Justice wholly educated in Australia. His career covered academic, political and legal realms. He was involved in the establishment of the Sydney University Law School. He campaigned for the Federation of Australia. He supported the admission of women as lawyers. His extended term as Acting Governor of New South Wales coincided with one of the worst periods experienced by Australians in the First World War. The sense of public duty he inherited from his family was fostered by his educational experiences, producing a lawyer of the highest calibre, with a powerful social conscience, actively involved in shaping the character of the modern Australian legal profession.