London in special for different reasons, yes. My main point though was that Vienna's population decreased greatly after its empire, and while increasing is sti

London in special for different reasons, yes. My main point though was that Vienna's population decreased greatly after its empire, and while increasing is still 10% smaller than a century ago. London's population has different dynamics, and I can't pretend to have a good reason. I can observe that https://en.wikipedia.org/wiki/Demography_of_London https://en.wikipedia.org/wiki/Demography_of_London shows a clear decline correlating with its shift away from being an imperial power, from ~8 million in 1951 to ~6.6M 1981.