This database covers immigration-related demographic data for 7 Western European countries (Austria, Belgium, Ireland, Netherlands, Spain, Switzerland, and United Kingdom) between 1990 and 2009. A number of indicators are included to cover the following aspects: (1) a general overview about the immigrant population in the selected countries (2) information about numbers of immigrants entering and settling in the selected countries (3) information about the backgrounds of immigrants, such as countries of origin, religious backgrounds, gender and education. The data were collected as part of the FP7-funded project Support and Opposition to Migration (http://www.som-project.eu/)