This paper identifies autochthony—the belief that a place belongs to its original inhabitants and that they are therefore more entitled—as a relevant new determinant of out-group prejudice. We hypothesized that autochthony uniquely predicts prejudice towards migrant groups and that it mediates the relationship between national identification and prejudice. The mediation process was anticipated to be especially strong for people who perceive out-group encroachment, that is, those who feel that immigrants are ‘getting out of place’. These hypotheses were tested in two studies using nationally representative samples of native Dutch participants. In Study 1 (N = 793), we showed that autochthony is an empirically distinct construct and that it is a unique predictor of prejudice. Furthermore, higher national identifiers expressed stronger claims of autochthony, and these claims were in turn associated with more negative feelings towards migrant groups. Study 2 (N = 466) showed support for a moderated mediation model: Beliefs in autochthony were only related to prejudice for participants who perceived out-group encroachment. Copyright © 2013 John Wiley & Sons, Ltd.