The characters of Anne, Matthew, Marilla, Diana, Gilbert, and Rachel Lynde all originated from Lucy Maud Montgomery's novel. Felicity and Hettie King originated from the 1990 series "Road to Avonlea." Everyone else was created specifically for this show.
Anne is the only character to appear in every episode.
While the "Anne of Green Gables" books were set in the late 19th century, this series is set in the early 20th century, around 1903, with the advent of motor cars and flying machines.