The Anne of Green Gables series by L.M. Montgomery should be read in the following order:
- Anne of Green Gables (1908)
- Anne of Avonlea (1909)
- Anne of the Island (1915)
- Anne of Windy Poplars (1936)
- Anne's House of Dreams (1917)
- Anne of Ingleside (1939)
- Rainbow Valley (1919)
- Rilla of Ingleside (1921)
For further details, you can check the source here.