The Tale of Johnny Town-Mouse was published in December 1918 by Frederick Warne & Co and was based on the Aesop fable ‘The Town Mouse and the Country Mouse’. In 1917 Potter was too busy tending to her farm duties to consider creating a new book, but the following year she was able to produce her last work which featured an entirely new set of drawings. The author proposed Timmy Willie or The Tale of a Country Mouse as possible titles for the book, though they were rejected by her publisher. Potter borrowed heavily from her life while working on her illustrations, including modelling the carrier’s horse in the book on Diamond, a horse working at Hill Top and using a friend, Dr Parsons, as the inspiration for Johnny Town-Mouse. The golf clubs that the eponymous character is seen carrying on the front cover of the book is a reference to the private golf course that Dr Parsons had built in Sawrey.
The plot follows Timmy Willie, a country mouse, who falls asleep and is accidently taken in a hamper to the city, where he is left in the kitchen of a town house. He falls through a ceiling and encounters Johnny-Town-Mouse and his friends. The story then recounts Timmy Willie’s impressions of city life and how he interprets his experiences in this unfamiliar setting; this is then compared and contrasted to Johnny Town-Mouse’s stay in the country. Potter does not feign impartiality with regards to her preference for the country way of life over city living. She presents the country far more attractively than the city and reveals Timmy Willie’s fears of predators in town to be real, while Johnny Town-Mouse’s reservations about the country are portrayed as irrational. Living in the country is presented as far healthier, purer and more innocent than the dangers and corruption of the city.