Walt Disney conceived the film during a trip to Ireland with the Irish Folklore Commission in 1947. The following year, Disney announced he would make a film titled "Three Wishes", based on a script from Watkin about an Irishman battling a leprechaun, which was to involve both live action and animation. However, the script was never produced. Disney took a second trip to Ireland in 1956 and announced a new film that October, "The Three Wishes of Darby O'Gill", based on Kavanagh's 1903 book "Darby O'Gill and the Good People", retaining Watkin as writer. Disney studied Gaelic folklore for three months at the Dublin Library and received input from "seanchaí" while developing the film. During casting in London in February 1958, the film's title became "Darby O'Gill and the Little People".