o'reilly joined the newspaper enterprise association in 1913, as a foreign correspondent; she worked from the association's london office, but traveled to both russia and mexico to report stories in 1913. in 1914 she conducted the first interview with joseph caillaux, the french politician, after his wife confessed to killing journalist gaston calmette. in 1915, king haakon vii of norway spoke to o'reilly about his country's neutrality during world war i. in 1916 she interviewed lady ernest shackleton about her husband's missing expedition to antarctica.