Quantifying the Muslim population in Europe: Conceptual and data issues

A review of the growing literature on the Muslim population in Europe shows that it remains poorly captured in official statistics. There is no authoritative map of the distribution of Muslims in Europe, and little quantitative evidence on their demographic, social or economic characteristics. This paper undertakes a systematic review of the conceptual and methodological issues surrounding the quantification of Muslim populations. With few countries routinely collecting data on religious affiliation, this is generally based on an estimation of the association between religion and some other measure of identity, such as country of birth or nationality. The rationale for the various 'religiousproxy' methods, and their limitations, is discussed in relation to the range of different data regimes observed across the region. The paper argues that changes in the political status of Muslim populations (following naturalization) and the manner of their growth (increasingly driven by natural increase) have meant that in statistical terms, they represent a disappearing target. The paper concludes that meaningful statistics on the Muslims in Europe will increasingly depend on the direct measurement of religious affiliation.