Martinius Nielsen was born on January 23, 1859 in Copenhagen, Denmark as Martinus Valdemar Nielsen. He was a director and actor, known for Den grønne Bille (1918), Tidens Barn (1918) and Gentlemansekretæren (1916). He was married to Oda Nielsen. He died on July 10, 1928 in Fredensborg, Denmark.