While searching Google for a good map of Switzerland, I stumbled upon a map called “Muslimkarte”. Being an avid reader of strangemaps (a blog which, as the name says, collects all kind of strange and interesting maps), I couldn’t resist to investigate this particular map for a bit. The map is hosted on winkelried.info, which seems to be a site closely associated with the SVP, a national conservative political party in Switzerland.

Source: Muslimkarte Schweiz
Cantons (administrative districts of Switzerland) whose Muslim population is above 4% of the general population are rendered green. The average for Switzerland is given as 4.5%. Below the map, the text assorts that in Europe (beside the countries of the Balkan region) only France has a higher percental of Muslims.
Unfortunately, the map has some flaws and errors:
* First, the average for Switzerland is 4.26%, according to the Federal Statistical Office (FSO) of Switzerland.
* Second, the assumption that Switzerland has the second highest percental Muslim population is factually wrong. France has indeed a higher percentage than Switzerland, but so do the Netherlands (5%) and Austria (4.8%). And the numbers for Germany (4%), Liechtenstein (4%), Sweden (3.9%) and Belgium (3.8%) aren’t so far away from Switzerland’s average. Sources: Wikipedia: Muslims in Western Europe, Wikipedia: Islam in Liechtenstein.
* In addition to these errors, the use of a 4% as a threshold seems a bit arbitrary.
Thus I tried to address these points and made my own version of the map. As basis for my work, I used the data provided by the FSO in its report Wohnbevölkerung nach Religion, nach Kantonen und Städten, which is available as Excel sheet (at the bottom of the page). The same sheet together with my calculations can also be downloaded.
Taking the average of 4.26%, I chose to highlight cantons whose Muslim population is above average (meaning at least 10% higher than the Swiss average) in dark blue. Cantons with an average percentage (meaning their average differs by more or less than 10% to the Swiss average) in light violet. Cantons which are below average are in grey. Here’s the resulting map:
The two maps look similar, yet the Canton of Lucerne is included in the original map, but actually is below average by my calculations. Overall, I believe my method to be more representative. Still, the possible room for interpretation is pretty limited:
* The Muslim population is more represented in the cantons along the Swiss-German border, as well as in and around the Canton of Geneva. Maybe this means that many of them come from or through Germany and France? Both countries have large Muslim populations (Germany: approx. 3.3 Mio; France: approx. 6 Mio.).
* The most obvious correlation of the Muslim population in Switzerland is with the greater metropolitan area of Zurich, which is also the most important economical area of Switzerland. However, correlation does not imply causation.
And that’s about it. Maybe some further studies could help to understand the distribution of Switzerland’s Muslim population better? The data avaible through the FOS is pretty limited itself, breaking these numbers down to a city or municipality level could offer a broader picture.