Romanus was born on 19 January 1906 in Karlstad, Sweden, the son of lector Anton Romanus and his wife Reidunn. He was uncle of Gabriel Romanus. Romanus passed studentexamen in Östersund in 1924. Romanus received a Candidate of Law degree in Stockholm in 1929 and worked as a law clerk in the Svea Court of Appeal in 1929, became an assessor in 1939, and was director in the Ministry of Justice from 1944 to 1947. Romanus was appointed Hovrättsråd in 1946 and was a member of the Swedish state legislative committee from 1947 to 1950. He served as a Justice of the Supreme Court of Sweden from 1951 to 1973, as department chairman in the Supreme Court in 1966, and as President of the Supreme Court of Sweden from 1969 to 1973. Romanus was Minister for Justice and head of the Ministry of Justice from 1976 to 1979. Romanus was also a member, secretary, chairman etc of different committees, commissions, investigations, and councils. He was notary and secretary in various Parliamentary committees in the Riksdag from 1936 to 1942, a substitute in the Labour Court in 1941 and vice chairman from 1949 to 1950. Romanus was assigned to the Ministry of Ecclesiastical Affairs and in Ministry of Justice from 1941 to 1943, was secretary of the 1941 års befolkningsutredning from 1941 to 1944, the Parliamentary Investigation Commission from 1945 to 1947, and served as Deputy Justice Ombudsman from 1948 to 1949. Furthermore, Romanus was vice chairman of the Swedish Press Council from 1956 to 1959, chairman there from 1960 to 1976, chairman of the Swedish Youth Correctional Board from 1958 to 1969, of the Council on Legislation from 1962 to 1964, of the Kommittén för lagstiftning om yttrande- och tryckfrihet from 1965 to 1972, if the Massmedieutredningen from 1970 to 1976, of the Programrådet för radioaktivt avfall from 1980 to 1981, and of the Nämnden för hantering av använt kärnbränsle from 1981 to 1984.
Personal life
In 1932 he married Alfhild Sandfærhus, the daughter of Hans Sandfærhus and Kari. They had three children: Barbro, Kurt and Gunilla.