I’ve compared Columbus to peer cities nationally in terms of density and population, but I’ve never made a Midwest cities historic population and density comparison overall. For the following, I used the top 15 largest Midwest cities as of 2014.

Red indicates a fallen ranking while blue indicates a rise. Black is no change.

Historic Population Rankings
1840
1. Cincinnati: 46,338
2. St. Louis: 16,469
3. Detroit: 9,102
4. Cleveland: 6,071
5. Columbus: 6,048
6. Chicago: 4,470
7. Indianapolis: 2,695
8. Milwaukee: 1,700
9. Toledo: 1,222
10. Kansas City: Not incorporated.
11. Lincoln: Not incorporated.
12. Minneapolis: Not incorporated.
13. Omaha: Not incorporated.
14. St. Paul: Not incorporated.
15. Wichita: Not incorporated.

1850
1. Cincinnati: 115,435
2. St. Louis: 77,860
3. Chicago: 29,963
4. Detroit: 21,019
5. Milwaukee: 20,061
6. Columbus: 17,882
7. Cleveland: 17,034
8. Indianapolis: 8,091
9. Toledo: 3,829
10. St. Paul: 1,112
11. Kansas City: Not incorporated.
12. Lincoln: Not incorporated.
13. Minneapolis: Not incorporated.
14. Omaha: Not incorporated.
15. Wichita: Not incorporated.

1860
1. Cincinnati: 161,044
2. St. Louis: 160,773
3. Chicago: 112,172
4. Detroit: 45,619
5. Milwaukee: 45,246
6. Cleveland: 43,417
7. Indianapolis: 18,611
8. Columbus: 18,554
9. Toledo: 13,768
10. St. Paul: 10,401
11. Minneapolis: 5,809
12. Kansas City: 4,418
13. Omaha: 1,883
14. Lincoln: Not incorporated.
15. Wichita: Not incorporated.

1870
1. St. Louis: 310,864
2. Chicago: 298,977
3. Cincinnati: 216,239
4. Cleveland: 92,829
5. Detroit: 79,577
6. Milwaukee: 71,440
7. Indianapolis: 48,244
8. Kansas City: 32,260
9. Toledo: 31,584
10. Columbus: 31,274
11. St. Paul: 20,030
12. Omaha: 16,083
13. Minneapolis: 13,066
14. Lincoln: 2,441
15. Wichita: 689

1880
1. Chicago: 503,185
2. St. Louis: 350,518
3. Cincinnati: 255,139
4. Cleveland: 160,146
5. Detroit: 116,340
6. Milwaukee: 115,587
7. Indianapolis: 75,056
8. Kansas City: 55,785
9. Columbus: 51,647
10. Toledo: 50,137
11. Minneapolis: 46,887
12. St. Paul: 41,473
13. Omaha: 30,518
14. Lincoln: 13,003
15. Wichita: 4,911

1890
1. Chicago: 1,099,850
2. St. Louis: 451,770
3. Cincinnati: 296,908
4. Cleveland: 261,353
5. Detroit: 205,877
6. Milwaukee: 204,468
7. Minneapolis: 164,738
8. Omaha: 140,452
9. St. Paul: 133,156
10. Kansas City: 132,716
11. Indianapolis: 105,436
12. Columbus: 88,150
13. Toledo: 81,434
14. Lincoln: 55,164
15. Wichita: 23,853

1900
1. Chicago: 1,698,575
2. St. Louis: 575,238
3. Cleveland: 381,768
4. Cincinnati: 325,902
5. Detroit: 285,704
6. Milwaukee: 285,315
7. Minneapolis: 202,718
8. Indianapolis: 169,164
9. Kansas City: 163,752
10. St. Paul: 163,065
11. Toledo: 131,822
12. Columbus: 125,560
13. Omaha: 102,555
14. Lincoln: 40,169
15. Wichita: 24,671

1910
1. Chicago: 2,185,283
2. St. Louis: 687,029
3. Cleveland: 560,663
4. Detroit: 465,766
5. Milwaukee: 373,857
6. Cincinnati: 363,591
7. Minneapolis: 301,408
8. Kansas City: 248,381
9. Indianapolis: 233,650
10. St. Paul: 214,744
11. Columbus: 181,511
12. Toledo: 168,497
13. Omaha: 124,096
14. Wichita: 52,450
15. Lincoln: 43,973

1920
1. Chicago: 2,701,705
2. Detroit: 993,678
3. Cleveland: 796,841
4. St. Louis: 772,897
5. Milwaukee: 457,147
6. Cincinnati: 401,247
7. Minneapolis: 380,582
8. Kansas City: 324,410
9. Indianapolis: 314,194
10. Toledo: 243,164
11. Columbus: 237,031
12. St. Paul: 234,698
13. Omaha: 191,061
14. Wichita: 72,217
15. Lincoln: 54,948

1930
1. Chicago: 3,376,438
2. Detroit: 1,568,662
3. Cleveland: 900,429
4. St. Louis: 821,960
5. Milwaukee: 578,249
6. Minneapolis: 464,356
7. Cincinnati: 451,160
8. Kansas City: 399,746
9. Indianapolis: 364,161
10. Toledo: 290,718
11. Columbus: 290,564
12. St. Paul: 271,606
13. Omaha: 214,006
14. Wichita: 111,110
15. Lincoln: 75,933

1940
1. Chicago: 3,396,808
2. Detroit: 1,623,452
3. Cleveland: 878,336
4. St. Louis: 816,048
5. Milwaukee: 587,472
6. Minneapolis: 492,370
7. Cincinnati: 455,610
8. Kansas City: 400,178
9. Indianapolis: 386,972
10. Columbus: 306,087
11. St. Paul: 287,736
12. Toledo: 282,349
13. Omaha: 223,844
14. Wichita: 114,966
15. Lincoln: 81,984

1950
1. Chicago: 3,620,962
2. Detroit: 1,849,568
3. Cleveland: 914,808
4. St. Louis: 856,796
5. Milwaukee: 637,392
6. Minneapolis: 521,718
7. Cincinnati: 503,998
8. Kansas City: 456,622
9. Indianapolis: 427,173
10. Columbus: 375,901
11. St. Paul: 311,349
12. Toledo: 303,616
13. Omaha: 251,117
14. Wichita: 168,279
15. Lincoln: 98,884

1960
1. Chicago: 3,550,404
2. Detroit: 1,670,144
3. Cleveland: 876,050
4. St. Louis: 750,026
5. Milwaukee: 741,324
6. Cincinnati: 502,550
7. Minneapolis: 482,872
8. Indianapolis: 476,258
9. Kansas City: 475,539
10. Columbus: 471,316
11. Toledo: 318,003
12. St. Paul: 313,411
13. Omaha: 301,598
14. Wichita: 254,698
15. Lincoln: 128,521

1970
1. Chicago: 3,366,957
2. Detroit: 1,514,063
3. Cleveland: 750,903
4. Indianapolis: 744,624
5. Milwaukee: 717,099
6. St. Louis: 622,236
7. Columbus: 539,677
8. Kansas City: 507,087
9. Cincinnati: 452,525
10. Minneapolis: 434,400
11. Toledo: 383,818
12. Omaha: 346,929
13. St. Paul: 309,980
14. Wichita: 276,554
15. Lincoln: 149,518

1980
1. Chicago: 3,005,072
2. Detroit: 1,203,368
3. Indianapolis: 700,807
4. Milwaukee: 636,212
5. Cleveland: 573,822
6. Columbus: 564,871
7. St. Louis: 452,801
8. Kansas City: 448,159
9. Cincinnati: 385,460
10. Minneapolis: 370,951
11. Toledo: 354,635
12. Omaha: 313,939
13. Wichita: 279,272
14. St. Paul: 270,230
15. Lincoln: 171,932

1990
1. Chicago: 2,783,726
2. Detroit: 1,027,974
3. Indianapolis: 731,327
4. Columbus: 632,910
5. Milwaukee: 628,088
6. Cleveland: 505,616
7. Kansas City: 435,146
8. St. Louis: 396,685
9. Minneapolis: 368,383
10. Cincinnati: 364,040
11. Omaha: 335,795
12. Toledo: 332,943
13. Wichita: 304,011
14. St. Paul: 272,235
15. Lincoln: 191,972

2000
1. Chicago: 2,896,016
2. Detroit: 951,270
3. Indianapolis: 781,926
4. Columbus: 711,470
5. Milwaukee: 596,974
6. Cleveland: 478,403
7. Kansas City: 441,545
8. Omaha: 390,007
9. Minneapolis: 382,618
10. St. Louis: 348,189
11. Wichita: 344,284
12. Cincinnati: 331,285
13. Toledo: 313,619
14. St. Paul: 287,151
15. Lincoln: 225,581

2010
1. Chicago: 2,695,598
2. Indianapolis: 829,445
3. Columbus: 787,033
4. Detroit: 713,777
5. Milwaukee: 594,833
6. Kansas City: 459,787
7. Omaha: 408,958
8. Cleveland: 396,815
9. Minneapolis: 382,578
10. Wichita: 382,368
11. St. Louis: 319,294
12. Cincinnati: 296,945
13. Toledo: 287,208
14. St. Paul: 285,068
15. Lincoln: 258,379

2014
1. Chicago: 2,722,389
2. Indianapolis: 848,788
3. Columbus: 835,957
4. Detroit: 680,250
5. Milwaukee: 599,642
6. Kansas City: 470,800
7. Omaha: 446,559
8. Minneapolis: 407,207
9. Cleveland: 389,521
10. Wichita: 388,413
11. St. Louis: 317,419
12. Cincinnati: 298,165
13. St. Paul: 297,640
14. Toledo: 281,031
15. Lincoln: 272,996

2020 Projection based on recent estimates.
1. Chicago: 2,736,032
2. Columbus: 905,875
3. Indianapolis: 873,774
4. Detroit: 646,682
5. Milwaukee: 606,730
6. Kansas City: 494,731
7. Omaha: 460,487
8. Minneapolis: 445,321
9. Wichita: 395,751
10. Cleveland: 380,149
11. St. Louis: 308,348
12. St. Paul: 306,448
13. Cincinnati: 302,288
14. Lincoln: 297,136
15. Toledo: 270,837

Columbus seems poised to take the #2 spot from Indianapolis around or just after 2020. Also, 11 of 15 would’ve seen growth 2010-2020. Cleveland, Toledo, St. Louis and Detroit would be the only cities that still lost.

2014 Density
1. Chicago: 11,634.1
2. Minneapolis: 6,972.7
3. Milwaukee: 6,188.3
4. St. Paul: 5,296.1
5. St. Louis: 4,809.4
6. Detroit: 4,760.3
7. Cleveland: 4,721.5
8. Omaha: 3,755.8
9. Columbus: 3,747.0
10. Cincinnati: 3,745.8
11. Lincoln: 3,620.6
12. Toledo: 3,246.1
13. Wichita: 2,374.2
14. Indianapolis: 2,306.5
15. Kansas City: 1,475.9

2020 Projected density using recent estimates.
1. Chicago: 11,692.4
2. Minneapolis: 7,625.4
3. Milwaukee: 6,261.4
4. St. Paul: 5,452.8
5. St. Louis: 4,671.9
6. Cleveland: 4,607.9
7. Detroit: 4,525.4
8. Columbus: 4,060.4
9. Lincoln: 3,940.8
10. Omaha: 3,872.9
11. Cincinnati: 3,797.6
12. Toledo: 3,220.4
13. Wichita: 2,419.0
14. Indianapolis: 2,374.4
15. Kansas City: 1,550.9

The Census is a great source if you are interested in seeing other cities that are not listed above.