In 1873 Zimmern began writing critical articles, particularly on German literature, for the Examiner. She also wrote for Fraser's Magazine, Blackwood's Magazine, the Athenaeum, the Spectator, St James's, Pall Mall Magazine, the World of Art, the Italian La Rassegna Settimanale and various German papers. Her advocacy and translations made European culture – whether of Germany, or increasingly Italy – accessible to English readers. She lectured on Italian art in Britain and Germany, and translated Italian drama, fiction and history. She befriended Friedrich Nietzsche, two of whose books she would later translate, in Switzerland in the mid-1880s. By the end of the decade she had settled in Florence, where she was associated with the Corriere della Sera and also edited the Florence Gazette. In later life she defended Italian values against what she saw as the threat of German expansionism.