FL has always been an interesting struggle. Jax was the big city of FL for a long time, and it wasn't until the middle of the 20th century when Jacksonville began to decline, relatively, and the Central and Southern portions of the state really exploded with transplants and immigrants.
Jacksonville's decline can be traced to 1948 when the first of a series of corrupt mayors took over and racism and bigotry ruled what was once one of the most liberal, high growth, and diverse cities in the country at that time. 1948 is the first year tolls were introduced on bridges leading into downtown. The 50s saw the paving over of the riverfront. The 60s and 70s saw large scale destruction of downtown. The city has not recovered since.
By county:
1830
Duval (Jax) 1,970
Escambia (Pensacola) 0
Hillsborough (Tampa) 0
Orange (Orlando) 0
Miami-Dade 0
1840
Duval (Jax) 4,156
Escambia (Pensacola) 3,933
Hillsborough (Tampa) 452
Miami-Dade 446
Orange (Orlando) 73
1850
Duval (Jax) 4,539
Escambia (Pensacola) 4,351
Hillsborough (Tampa) 2,377
Orange (Orlando) 466
Miami-Dade 159
1860
Escambia (Pensacola) 5,768
Duval (Jax) 5,074
Hillsborough (Tampa) 2,981
Orange (Orlando) 987
Miami-Dade 83
1870
Duval (Jax) 11,921
Escambia (Pensacola) 7,817
Hillsborough (Tampa) 3,216
Orange (Orlando) 2,195
Miami-Dade 85
1880
Duval (Jax) 19,431
Escambia (Pensacola) 12,156
Orange (Orlando) 6,618
Hillsborough (Tampa) 5,814
Miami-Dade 257
1890
Duval (Jax) 26,800
Escambia (Pensacola) 20,188
Hillsborough (Tampa) 14,941
Orange (Orlando) 12,584
Miami-Dade 861
1900
Duval (Jax) 39,733
Hillsborough (Tampa) 36,013
Escambia (Pensacola) 28,313
Orange (Orlando) 11,374
Miami-Dade 4,955
1910
Hillsborough (Tampa) 78,374
Duval (Jax) 75,163
Escambia (Pensacola) 38,029
Orange (Orlando) 19,107
Miami-Dade 11,933
1920
Duval (Jax) 113,540
Hillsborough (Tampa) 88,257
Escambia (Pensacola) 49,386
Miami-Dade 42,753
Orange (Orlando) 19,890
1930
Duval (Jax) 155,503
Hillsborough (Tampa) 153,519
Miami-Dade 142,955
Escambia (Pensacola) 53,394
Orange (Orlando) 49,737
1940
Miami-Dade 267,739
Duval (Jax) 210,143
Hillsborough (Tampa) 180,148
Escambia (Pensacola) 74,667
Orange (Orlando) 70,074
1950
Miami-Dade 495,084
Duval (Jax) 304,029
Hillsborough (Tampa) 249,894
Orange (Orlando) 114,950
Escambia (Pensacola) 112,706
1960
Miami-Dade 935,047
Duval (Jax) 455,411
Hillsborough (Tampa) 397,788
Orange (Orlando) 263,540
Escambia (Pensacola) 173,829
1970
Miami-Dade 1,267,792
Duval (Jax) 528,865
Hillsborough (Tampa) 490,265
Orange (Orlando) 344,311
Escambia (Pensacola) 205,334
1980
Miami-Dade 1,625,781
Hillsborough (Tampa) 646,960
Duval (Jax) 571,003
Orange (Orlando) 471,076
Escambia (Pensacola) 233,794
1990
Miami-Dade 1,937,094
Hillsborough (Tampa) 834,054
Orange (Orlando) 677,491
Duval (Jax) 672,971
Escambia (Pensacola) 262,798
2000
Miami-Dade 2,253,362
Hillsborough (Tampa) 998,848
Orange (Orlando) 896,344
Duval (Jax) 778,879
Escambia (Pensacola) 294,410
2010
Miami-Dade 2,496,435
Hillsborough (Tampa) 1,229,226
Orange (Orlando) 1,145,956
Duval (Jax) 864,263
Escambia (Pensacola) 297,619
By Current Metro boundaries:
1830
Jacksonville 1,970
Pensacola 0
Tampa 0
Orlando 0
South Florida 0
1840
Jacksonville 8,742
Pensacola 3,933
Tampa 452
South Florida 446
Orlando 73
1850
Jacksonville 9,228
Pensacola 7,234
Tampa 3,303
Orlando 466
South Florida 159
1860
Jacksonville 13,670
Pensacola 11,248
Tampa 4,181
Orlando 987
South Florida 83
1870
Jacksonville 22,209
Pensacola 11,129
Tampa 6,154
Orlando 2,195
South Florida 85
1880
Jacksonville 35,742
Pensacola 18,801
Tampa 10,062
Orlando 6,618
South Florida 257
1890
Jacksonville 52,293
Pensacola 28,149
Orlando 23,751
Tampa 21,666
South Florida 861
1900
Jacksonville 68,703
Tampa 45,705
Pensacola 38,606
Orlando 22,285
South Florida 4,955
1910
Jacksonville 109,817
Tampa 90,873
Pensacola 52,926
Orlando 34,123
South Florida 17,510
1920
Jacksonville 149,184
Tampa 129,872
South Florida 66,542
Pensacola 63,056
Orlando 50,815
1930
Tampa 231,190
South Florida 214,830
Jacksonville 196,686
Orlando 102,332
Pensacola 67,477
1940
South Florida 387,522
Tampa 291,629
Jacksonville 253,959
Orlando 129,752
Pensacola 90,752
1950
South Florida 693,705
Tampa 436,365
Jacksonville 362,474
Orlando 189,579
Pensacola 131,260
1960
South Florida 1,497,099
Tampa 820,443
Jacksonville 529,532
Orlando 394,899
Pensacola 203,376
1970
South Florida 2,236,645
Tampa 1,105,553
Jacksonville 621,519
Orlando 522,575
Pensacola 243,075
1980
South Florida 3,220,844
Tampa 1,613,603
Orlando 804,985
Jacksonville 737,541
Pensacola 289,782
1990
South Florida 4,056,100
Tampa 2,067,959
Orlando 1,224,852
Jacksonville 925,213
Pensacola 344,406
2000
South Florida 5,007,564
Tampa 2,395,897
Orlando 1,644,561
Jacksonville 1,122,750
Pensacola 412,153
2010
South Florida 5,564,635
Tampa 2,783,243
Orlando 2,134,411
Jacksonville 1,345,596
Pensacola 448,991