How do immigration and birth rates each contribute to Muslim population growth in Europe since 2000?
Executive summary
Since 2000, Europe’s rising Muslim population has been driven chiefly by international migration into Europe and secondarily by higher fertility among Muslims compared with non-Muslims, with the relative weight of those two factors varying by country and over time; projections from Pew and demographic researchers show fertility gaps narrowing over generations while migration remains the most variable and immediate source of growth [1] [2] [3].
1. Immigration: the primary short‑term engine of growth
The single clearest contributor to increases in the number and share of Muslims in Europe since 2000 has been immigration — large flows from Turkey, North Africa, South Asia and later asylum seekers from Syria and other conflict zones — which created rapid upticks in Muslim populations in many Western and Northern European countries [4] [2] [1]; because migration changes population size immediately, spikes in arrivals (for example the mid‑2010s refugee wave) produced measurable jumps that births alone could not explain [2] [3].
2. Fertility: higher now, converging over time
Muslim women in Europe have tended to have higher total fertility rates than native non‑Muslim women, contributing steadily to Muslim population growth, but multiple studies and Pew projections find that these fertility gaps shrink across second and third generations as immigrant families’ fertility “falls in parallel” with host‑country norms, so the long‑term contribution from births alone is projected to decline though remain above native rates for decades [5] [6] [2].
3. Age structure and momentum amplify births’ effect
Beyond per‑woman fertility differences, the Muslim population’s younger age profile means a larger share of people are in childbearing ages, producing demographic momentum: even with fertility converging, a younger cohort mix leads to more births today than would occur in an older population, which is why zero‑migration scenarios still show some Muslim population increase from births in Pew’s models [2] [3].
4. Regional nuance: not a single European story
Patterns differ sharply across Europe: in Eastern Europe much Muslim growth reflected post‑Communist religious revival and movements within former Soviet states, while in Western Europe growth has been concentrated in countries with sustained immigration and established immigrant networks (France, Germany, UK, Netherlands) — meaning immigration explains much of the variation between countries, and fertility differentials are themselves influenced by education, socioeconomic status and length of settlement [4] [5] [6].
5. Projections, uncertainty and contested narratives
Pew’s 2016 baseline and its alternative migration scenarios demonstrate that migration policy and future crises are the largest sources of uncertainty: under “zero migration” Muslim shares grow modestly through births and age structure, whereas high‑migration scenarios produce much larger increases, which is why Pew frames the exercises as conditional projections not ironclad predictions [2] [3]. Some analysts and outlets amplify worst‑case language or focus on high fertility as an existential threat; others emphasize rapid convergence and data gaps — both positions can cherry‑pick the same underlying studies [7] [8].
6. Measurement limits, political stakes and hidden agendas
Estimating religion across Europe is fraught because many national censuses don’t ask religion and survey sampling must reconstruct identity from imperfect data, which introduces uncertainty that political actors can exploit: immigration‑skeptical policymakers and alarmist media may overstate fertility’s role, while advocates for migrants may underplay short‑term migration impacts; good demographic reporting therefore needs to cite cohort models, migration scenarios and the documented trend of fertility decline among later generations [3] [8] [9].