Edward Samuel Caswell was a Canadian librarian, publisher, and editor.
He was born in Goderich, Ontario (at that time Canada West) in 1861.
He was for many years the manager of the book publishing department of the Methodist Book and Publishing House in Toronto (which later evolved into the Ryerson Press), and in that capacity did much to advance literature in Canada.
Among the writers he championed were William Wilfred Campbell, Isabella Valancy Crawford, Agnes Christina Laut, Charles Mair, Nellie McClung, Catharine Parr Traill, and Ethelwyn Wetherald.
He worked subsequently at the Toronto Public Library and died in 1938.