How diverse were European cities in the early 20th century?

[Docere]

Originally Posted by eschaton

Istanbul seems like it was pretty diverse judging by the Ottoman 1914 Census.

As general background, the Ottomans only asked about religion, not ethnicity, thus they didn't distinguish between Muslims who were Turks, Arabs, Kurds, etc. Anyway:

Muslim: 61.9%
Greek Orthodox: 22.7%
Armenian Orthodox: 8.1%
Jews: 5.8%
Armenian Catholics: 1.1%
Others: 0.5%

Good find. Obviously much more diverse than today!