[1] Educated at St Joseph's College, Hunters Hill, he proved to be an all-round achiever, rowing in the winning school eight, and becoming captain of the Rugby Union football, cricket and athletics teams,.

[1] In 1928, he was appointed Editor-in-Chief of Smith's Weekly, replacing Claude McKay, building up its stable of black-and-white artists including Syd Miller,[4] Joe Jonsson,[1] Emile Mercier, Virgil Reilly, Rosaleen Norton, Marie 'Mollie' Horseman and Joan Morrison,[5] as well as giving great support to those already on the payroll — George Finey,[6] Frank Dunne, George Donaldson, and Stan Cross, who called him "the best Art Editor Australia ever had".

[1] Marien's second title was "Mechanical Superintendent" – he was a skilful fitter and turner and Linotype compositor, and a movie projectionist, with a well-equipped workshop and an 80-seat cinema at "Pine Lodge", his Miranda home.

[1][7] In 1932, he made a major error in not "pulling" the Wilkinson story, a lurid litany of untruths about the victim of a callous murder.

They had one daughter, Frances, and two sons, William and Brian, both of whom followed their father by rowing in winning "eights" at St Joseph's.