Which London boroughs have the highest Muslim shares and how does that compare to neighborhoods in Brussels and Rotterdam?

1. How London’s Muslim geography is portrayed — concentrated boroughs, diverse origins

The assembled analyses consistently identify Tower Hamlets, Newham, Redbridge and Waltham Forest among London’s boroughs with the largest Muslim shares, with Tower Hamlets reported at roughly 36–38% and Newham around 24–32% depending on the source ^{[1] [2]}. Other boroughs named repeatedly include Hackney, Brent, Ealing, Haringey, Barnet, Enfield and Camden, many of which register double‑digit Muslim shares or important local concentrations ^{[5] [1]}. The sources stress that London’s Muslim population is ethnically diverse — major South Asian components (Bangladeshi, Pakistani, Indian) alongside other backgrounds — and that citywide Muslim share estimates vary with census year and definition, with one source noting 15% in 2021 and another citing 12.4% in 2011, underscoring variation across data vintages ^{[5] [6]}.

2. Brussels’ picture — neighbourhood hotspots and socio‑economic stress

Brussels is presented in the analyses as having an overall Muslim share around 23% in one summary, but the operational detail focuses on neighbourhoods such as Molenbeek and Schaerbeek, described as recognized local centres with high youth unemployment and educational deficits — youth unemployment cited at roughly 27% in Molenbeek and 22% in Schaerbeek — rather than precise Muslim‑share percentages for each district ^{[3] [2]}. Reporting emphasizes that these districts are often highlighted in broader security and integration debates, with media coverage linking concentrated socio‑economic disadvantage to elevated risks of radicalisation; the supplied Washington Post summary frames these neighbourhoods as both high Muslim presence and high social risk without offering exact religion‑by‑neighbourhood figures ^[2].

3. Rotterdam’s outline — citywide share and community composition, but fewer neighbourhood figures

The materials convey that Rotterdam’s Muslim population is reported near 13% citywide, with Turkish and Moroccan communities identified as the largest groups within that share, and qualitative reporting that many Muslims in Rotterdam express a strong sense of belonging despite facing discrimination ^{[4] [7]}. The supplied reports come from monitoring and NGO studies that focus on lived experience — belonging, education, housing and employment — rather than producing a granular map of neighbourhood Muslim shares comparable to the London borough data. Consequently, the analyses note a clear gap: Rotterdam’s citywide percentage is supplied, but comparable small‑area percentages analogous to London boroughs or Brussels districts are absent from the provided material ^[4].

4. Comparing London, Brussels and Rotterdam — what can and cannot be concluded from the provided analyses

From the supplied content one can conclude that London contains boroughs with exceptionally high Muslim concentrations (up to roughly 36–38%), Brussels contains districts widely recognized for high Muslim presence and acute socio‑economic problems, and Rotterdam reports a moderate citywide Muslim share (~13%) with neighborhood‑level detail missing ^{[1] [2] [4]}. What cannot be reliably concluded from these analyses is a strict apples‑to‑apples numeric ranking of neighbourhoods across the three cities because the sources differ in scope, date and granularity: London borough percentages are given in some pieces, Brussels reporting emphasizes neighbourhood context and social indicators rather than exact shares, and Rotterdam is covered mainly at city level ^{[1] [2] [4]}.

5. Why gaps and timing matter — data vintage, measures and policy narratives

The analyses show variation by publication date and methodological focus: some London figures trace back to 2011 census snapshots or earlier reports, one summary cites 2021 citywide Muslim share, Brussels is summarized in recent government and media pieces focusing on socio‑economic risks, while Rotterdam is addressed in monitoring reports and NGO studies that emphasize social integration rather than demographic granularity ^{[6] [5] [3] [7]}. These differences shape headlines and policy narratives: high borough shares in London are often used to discuss service provision and community needs, Brussels neighbourhood metrics are mobilized in security and integration debates, and Rotterdam’s citywide framing informs inclusion and discrimination policy discussions; the absence of harmonized, recent neighbourhood‑level data across all three cities prevents definitive comparative rankings ^{[1] [2] [4]}.

6. Bottom line for readers seeking direct comparisons

Based on the provided analyses, the strongest factual claim is that London contains multiple boroughs with Muslim shares markedly higher than the citywide average — up to roughly 36–38% in Tower Hamlets and roughly 24–32% in Newham — while Brussels has well‑known high‑Muslim neighbourhoods like Molenbeek and Schaerbeek noted for socio‑economic disadvantage, and Rotterdam’s Muslim share is about 13% citywide ^{[1] [2] [3] [4]}. Any reader seeking a precise, up‑to‑date neighborhood‑by‑neighborhood numeric comparison across all three cities should note the data gaps and differing units of analysis in the supplied material and pursue harmonized, recent census or municipal small‑area datasets to draw firm, quantitative comparisons ^{[5] [6] [4]}.