One thing that stands out on this battlefield is that there is not a lot of troops covering a lot of area. As far as I can tell, for this war in Ukraine, each side has about 200,000 or so regular troops, after all new recruits and old losses are counted for. I actually have never seen any strength figures since the war has started. On the other hand, the Ukrainian Army has said that they have a front width of 2,450 kilometers (1,522 miles) of which 1,105 (687 miles) are active fighting. By active fighting, I assume that means the area from Kharkov to Severodonetsk to Kherson. The border with Belarus is 891 kilometers (554 miles), which I assume is part of the “inactive area.” The Ukrainian border with Russia is 1,974 kilometers (1,227 miles). Anyhow, not sure exactly how this active front is calculated, but I will use the Ukrainian Army figures for now (until I get the energy to pull out a ruler and painstakingly measure it myself).
So, 200,000 troops divided by 1,105 kilometers is 181 men per kilometer, except: I suspect that some of those people are protecting Kiev and other such places away from the active front, and some are in reserve and rear positions. So, it might be two-thirds of that figure (121 men per kilometer). This is less than a tenth of World War II standards for this area.
During the Battle of Kursk before 5 July 1943, in the south around Belgorod, the frontage from the German 332nd Infantry Division through Totenkopf (the main two-corps German attack) covered 54 kilometers. This was covered by 146,443 troops, for a density of 2,712 troops per kilometer. In contrast, the part of the Soviet Sixth Guards Army’s first echelon that was facing them consisted of only 46,412 troops or 859 troops per kilometer (see page 148 of my big Kursk book). This Sixth Guards Army defense, considering both echelons, came in at 1,301 men per kilometer covering 66 kilometers of front, while the neighboring Seventh Guards Army had 1,568 men per kilometer of front covering 55 kilometers (see page 210).
Just do a spot check of several division-level engagements (yes, I do have all this data for the southern Kursk and the Kharkov battles in 1943 in our database, the Division-Level Engagement Data Base or DLEDB): 1) the linear density of the LSSAH Panzer Grenadier Division on 12 July 1943 at the tank fields of Prokhorovka was 1,922.64 men per kilometer of front. The attacking Soviet 18th and 29th Tank Corps came in at 3,151.27 men per kilometer of front, 2) The linear density of men for the GD Panzer Division, 332nd ID and 3rd PzD attack on 5 July 1943 was 2,204.88 men per kilometer of front. It was 612.89 for the defending Soviet 71st Guards Rifle Division. Going to the battles around Kharkov, 3) the linear density of the Soviet 40th Army at Prudyanka-Dergachi on 12 February 1943 was 203.65 while the defending German GD ID was 510.38. 4) The linear density of the LSSAH assault on Kharkov on 12 March 1943 was 753.04 while the defending Soviet 19th Rifle Division, 17th NKVD Brigade and 86th Tank Brigade was 472.65. By the 14th, this had increased to 2,436.43 for the Germans and 1,739.29 for the defending Soviets, 5) The most sparsely deployed unit I have in my database for the fighting in and around Kharkov in February to August 1943 was 280.00 men per kilometer for the attacker and 169.75 for the defender at Merafa III engagement on 13 March 1943. 6) the densest is the 106th ID Defense III on 20 August 1943 with the attacking Soviet 48th Guards Rifle Corps and 375th RD deployed at 3,457.80 men per kilometer of front while the defending 106th ID was at 1,766.00 men per kilometer of front (I do have 3,649.13 for the attacker South of Kharkov on 15 March, but the defender only has 424.38). 7) The most sparsely deployed engagement I have for the Kursk fighting is nominally Soldatskoye VIII on 18 July 1943, where the attacking Soviet elements held a front of 392.25 men per kilometer and the defending German 255th ID held the front at 319.33 men per kilometer (there are a number of other engagements where one side had less density than these) 8) the densest engagement is LSSAH Division’s clash with the 31st Tank Corps on 7 July 1943, where the Germans had a density of 8.,475.00 men per kilometer and the Soviets were at 4,328.85 men per kilometer. This is mostly driven by the LSSAH frontage being temporarily reduced to 2.6 kilometers. This is all drawn from 256 division-level battles on the Eastern Front in February-August 1943 (192 from Kursk and 64 from Kharkov), with all the data drawn from the unit records of both sides. The average for the front now in Ukraine may be 121 men per kilometer, and they are not evenly distributed.
So, what does this all mean?
Well, from a theoretical point of view, it is showing the changes in linear density over time. As firepower increases, density of troop deployments decrease. This has been occurring for hundreds of years. See Dispersion versus Lethality | Mystics & Statistics (dupuyinstitute.org) and TDI Friday Read: Lethality, Dispersion, And Mass On Future Battlefields | Mystics & Statistics (dupuyinstitute.org) and The Effects Of Dispersion On Combat | Mystics & Statistics (dupuyinstitute.org). Also see my book War by Numbers.
From a more practical point of view, that means that there are many places that are holding their lines with less than 121 men per kilometer. Does this mean that any concentrated offensive force can push through these areas “if they achieve surprise.” So, should we be seeing more fluid lines?
But, in fact, we are not seeing more fluid lines. This looks less fluid than I expected. So why? Is it because U.S. intel assistance is so good that any concentration of force is immediately fired upon? Is it because any concentration of force is immediately spotted and responded to, by either firepower or movement of reserves?
I don’t really know for sure, just looking at linear densities.