Thornton Lacey (one of the parishes destined for Edmund Bertram once he is ordained) is a fictional location. However its bi-partite structure is very characteristic of many English village names. Indeed, there are several villages in England which have Thornton as their first part, including Thornton Curtis, Thornton Hough and Thornton Steward. There are also English villages named Lacey Green and Mansel Lacy.
Other intriguingly-named English villages which follow the same bi-partite pattern are: Ainderby Quernhow; Ewyas Harold; Farleigh Wallop; Maiden Bradley; Moreton Pinkney; Newton Bromswold; Swaffham Bulbeck; and Weare Giffard.