WereMaurice Elvey and Arthur Lubin both from the USA?
Maurice Elvey Maurice Elvey (11 November 1887 – 28 August 1967) was the most prolific film director in British history. He directed nearly 200 films between 1913 and 1957. During the silent film era he directed as many as twenty films per year. He also produced more than fifty films - his own as well as films directed by others.
Arthur Holch Arthur Everett Holch, Jr. [pronounced Holtsch] (March 13, 1924 – September 23, 2010) was an American television documentary filmmaker whose works in the early days of television covered controversial topics relating to race relations and political issues in the United States. Holch earned an Emmy Award for a 1991 documentary broadcast on HBO documenting the life of a German man who had been a member of the Hitler Youth and then turned against the Nazis.