Four Thousand Years of Urban G has put together a list of the Top 10 Largest Cities in Terms of Population in the Year 1900 After B.C. Check out the list below.
1
United Kingdom: 6,480,000
***2
United States: 4,242,000
***3
France: 3,330,000
***4
Germany: 2,707,000
***5
United States: 1,717,000
***6
Austria: 1,698,000
***7
Japan: 1,497,000
***8
Russia: 1,439,000
***9
United Kingdom: 1,435,000
***10
United States: 1,418,000
*** 
