Very good quiz - nice job! The one I find most interesting, and would never have expected, is the city which was the largest in Florida from 1880-1890, given its relative size today.
I scored 53/90 as a non-American. I consider it a fun challenge to finally list cities other than the state capitals. It is not my goal to remember the ones I didn't know :)
This quiz is definitely missing Lexington, Kentucky, which was the largest city in Kentucky in the 2000 census, with a population of 260,512 compared to Louisville's 256,231. (Louisville regained the title of biggest city in Kentucky after it consolidated with Jefferson County in 2004)
another error: Norfolk, Virginia became the biggest city in Virginia in 1960, not 1950. in the 1950 census, Richmond had around 230,000 while Norfolk had around 213,000
You made some mistakes for Mississippi. Natchez was the largest city from 1820-1860. Vicksburg was the largest city from 1870-1900. Meridian was the largest city from 1910-1920. Jackson has only been the largest city in Mississippi since the 1930 census.
Still a great quiz idea though.
Perhaps another 30 seconds? I couldn't finish on mobile.
This list only contains 23 state capitals.
another error: Norfolk, Virginia became the biggest city in Virginia in 1960, not 1950. in the 1950 census, Richmond had around 230,000 while Norfolk had around 213,000