[kiiski]

Wikipedia claims that "In 1950, New York City was the only urban area with a population of over 10 million."

https://en.wikipedia.org/wiki/Megacity#Growth

[24gttghh]

Even today, NYC's Five boroughs are <9 Million[0].

1920 Tokyo: 3.7 million[1]

1950 Shanghai: 6.2 million[2]

1971 Mumbai: 5.9 million[3]

1921 Greater London: 7.5 million[4]; Inner London: 4.9 million

Terms like Metro-area and Megalopois are different stories...

[0]https://www1.nyc.gov/site/planning/data-maps/nyc-population/...

[1]http://www.metro.tokyo.jp/ENGLISH/ABOUT/HISTORY/history03.ht...

[2]https://en.wikipedia.org/wiki/Demographics_of_Shanghai

[3]https://en.wikipedia.org/wiki/Mumbai#Demographics

[4]https://en.wikipedia.org/wiki/Demography_of_London