A map full of striking patterns, from Savills’ analyst Neal Hudson. It shows the areas of London where, for each area, the second most popular language is spoken by more than 5% of residents there, based on the 2011 Census. It clearly reveals London’s linguistic clusters, from Arabic to Yiddish and Lithuanian to Tamil.
The full-size map is no longer on Neal’s website but you can download it here.
Note that this is not a map of people’s own second languages, but rather of the second most popular language spoken in each area. The areas used are Middle Super Output Areas which have a typical population of around 10000 people, so, as a guide at least 500 people within each area speak the language shown as their primary language. Middle Super Output Areas are a statistical grouping of areas. They are somewhat analogous to political wards, except that they change if their populations decrease below, or increase above, thresholds, whereas wards tend to remain constant.