[1] Born at Cedar Rapids, Iowa[2] into a wealthy family from Chicago,[3] he studied at Northwestern University, Evanston, Illinois.
In the 1929 stock market crash, O'Hara and his whole family lost their fortunes, but he continued to work in a brokerage house and write and publish poetry.
His own poetry collections, such as Songs of the Open (1909), Pagan Sonnets (1913), Manhattan (1915), Threnodies (1918) and Embers (1921), received favorable notice.
[3] O'Hara was active in the poetical circles of his day and carried on an extensive correspondence with several women writers, most notably Sara Teasdale, Corinne Roosevelt Robinson, Jessie Belle Rittenhouse, Blanche Shoemaker Wagstaff and Leonora Speyer.
[3] The first stanza of his poem Atavism (1902)[4] is used as the epigraph to Jack London's The Call of the Wild: Old longings nomadic leap, Chafing at custom's chain; Again from its brumal sleep Wakens the ferine strain.