[1] He is known for his work on the economic history of the migration of British capital[2] and of the American railroad in the 19th century.
In the year 1920/21 he studies at the London School of Economics, and in 1927 received his PhD from Columbia University.
In 1917 Jenks had started his academic career as instructor in history at the University of Minnesota.
From 1919 to 1920 he was Assistant Professor of History and Political and Social Science at Clark College, before his year in London.
Back in the States he became Associate Professor of History and Social and Economic Institutions at Amherst College.