Complex sentence: Farnan's home was de Valera's first hideout in 1919 after his escape from Lincoln Gaol; Farnan warned de Valera that his "external association" alternative to the Anglo-Irish Treaty was too subtle to persuade the public.
Split into simpler sentences: Farnan's home was de Valera's first hideout in 1919 after his escape from Lincoln Gaol. He warned de Valera that his "external association" alternative to the Anglo-Irish Treaty was too subtle to persuade the public.